OPINION
MATTHEWS, Justice.
This is an action for a declaratory judgment brought by an association representing various title insurance companies, individual title insurance companies, and several landowners against the State of Alaska, the Municipality of Anchorage, and Theo[716]*716dore and Clair Pease. Nine claims for relief were presented.
The first claim sought a determination that a title insurance policy issued by Transamerica Title Insurance Company to the Peases excluded from coverage any rights-of-way created pursuant to certain Inferior Department Orders, namely, Public Land Orders 601, 757,1613, and Departmental Order 2665.
The second claim for relief sought a declaration that claimed easements for “local roads” as defined in DO 2665 could not be used by the State or municipal governments because of the Alaska Right of Way Act of 1966.
The third related to “feeder roads” as defined in PLO 601 and DO 2665, seeking a declaration that rights-of-way for such roads could not be utilized because of the Alaska Right of Way Act of 1966.
The fourth claim for relief concerned property owned by plaintiff Hansen Associates along the Seward Highway. It alleged that the original patentee had made a homestead entry prior to the effective date of the first order involved, PLO 601, and sought a declaration that no through road easement under PLO 601 or any of its successors could be claimed.
The fifth claim for relief referred to a quitclaim deed given on or about April 7, 1959, conveying the United States’ interests in the highways in Alaska to the State. The deed was recorded October 2, 1969. This claim sought a declaration that the quitclaim deed would have no effect on bona fide purchasers for value who purchased and recorded prior to the State’s recording of the quitclaim deed.
The sixth claim for relief alleged that the failure of the United States or the State to record PLOs 601, 757, and 1613 and DO 2665 in a State recording office rendered any easements that might otherwise have been created by those orders void as against subsequent innocent purchasers for value who first duly recorded their interests.
The seventh claim alleged a theory of estoppel against the State and Municipality, claiming that for twenty years they had allowed property owners to develop property on which they now claim an easement pursuant to PLOs 601, 757, and 1613 and DO 2665, that no notice of such claims had been given, and that individual property owners would be prejudiced if the State and the Municipality were now permitted to utilize such easements.
The eighth claim sought a declaration that no easement could be taken by the State or the Municipality for a local, feeder, or through road under the authority of PLOs 601, 757, and 1613 or DO 2665 because of the Right of Way Act of 1966.
The ninth claim alleged that prior to the quit-claim deed from the United States to the State of April 7,1959, the United States had patented to private landowners property which included rights-of-way now claimed by the State. A declaration was sought that these patents were conclusive as against the State and . that the patents could not be vacated or annulled because of the six year statute of limitations set forth in 43 U.S.C. § 1166.
The Peases cross-claimed against the State, alleging that the State unlawfully claimed a 50 foot road easement along the south boundary of their property whereas only a 33 foot easement was described in the patent from the United States to their predecessor-in-interest. They sought just compensation for the 17 foot difference in the approximate sum of $3,000.00 plus interest from the date of taking. The Peases also counterclaimed against Transamerica, alleging that if the State was entitled to a full 50 foot right-of-way Transamerica would be obliged under the title policy to compensate them for the value of the 17 foot strip.
Before answering, the State filed a motion for a more definite statement requesting legal descriptions of property across which the complaint alleged that the State was claiming rights-of-way. In response, the plaintiffs described the property owned by Hansen Associates along the Seward Highway, with respect to the fourth claim for relief, and property owned by plaintiff [717]*717Richard L. Boysen which also lay along the Seward Highway, with respect to the seventh claim. The State then answered the complaint, placing in controversy all the legal theories of the plaintiffs.
The State, all plaintiffs, and the Peases moved for summary judgment as to all claims. The court denied the State’s motion, granted the plaintiffs’ motion as to the second, third, and eighth claims, and granted the Peases’ motion as to their cross-claim and counterclaim. Following entry of a memorandum of decision reflecting these actions the court entered a declaratory judgment containing four numbered paragraphs, which proceed from the abstract to the particular. They are:
1. The State of Alaska and the Municipality of Anchorage are claiming highway easements for local, feeder, and through roads in excess of easement widths specified in patents issued to Alaska property owners. Said easements are claimed by the State or the Municipality pursuant to authority derived from Public Land Orders 601, 757, 1613 and Department Order 2665. For the reasons set forth in the Memorandum of Decision dated May 7, 1980, the court hereby awards Plaintiffs a summary judgment against the State of Alaska and the Municipality of Anchorage declaring that the State and the Municipality may not take or utilize property for local, feeder, or through roads in excess of the widths set forth in the patents to the affected properties without just compensation to the owners of the affected properties unless such local, feeder, or through roads were occupied and staked by the State of Alaska or the Municipality of Anchorage prior to April 14, 1966, or were specifically designated in the patents to the affected real properties.
2. The Plaintiffs Hanson [sic] Associates and Richard L. Boysen are hereby awarded a summary judgment against the State of Alaska and the Municipality of Anchorage declaring that neither the State nor the Municipality can take any portion of their properties for the through road presently known as the Old Seward Highway which is in excess of the easement widths specified in their respective patents without just compensation.
3. The Defendants Pease are hereby awarded a summary judgment on their cross-claim against the State of Alaska declaring that the State may not take or utilize any portion of the Peases’ land for the local road presently known as Rabbit Creek Road which is in excess of the 33-foot easement width specified in the patent to the Peases’ property without just compensation. The Peases’ property is described as Lot 191, Section 33, Township 12 North, Range 3 West, Seward Meridian, Anchorage Recording District, Third Judicial District, State of Alaska.
4. The Defendants Pease are hereby awarded a summary judgment on their counterclaim against Transamerica Title Insurance Company declaring that Trans-america is liable under its title insurance policy issued to the Peases for the taking by the State of Alaska of a 17-foot strip of land for the local road known as Rabbit Creek Road, which 17-foot strip of land was in excess of a 33-foot easement specified in the Peases’ patent. However, since the State of Alaska must compensate the Peases for the taking or utilization of said additional 17-foot easement, the Peases shall collect just compensation from the State of Alaska, and upon receipt of said just compensation the Peases shall not be entitled to recover damages from Transamerica Title Insurance Company for said taking of the additional 17-foot strip of property.
The State has appealed from this judgment. The plaintiffs have cross-appealed, claiming that the superior court should have granted them judgment on their fourth, fifth, sixth, seventh, and ninth claims for relief. In addition, Transamerica Title has appealed from the judgment against it in favor of the Peases.
I
THE STATE’S APPEAL AS TO THE PEASES’ PROPERTY
We turn first to the appeal of the State as it relates to the Peases’ property.
[718]*718The patent to the 2.5 acre Pease parcel was issued on October 4, 1955, pursuant to the Small Tract Act of 1938, 43 U.S.C. §§ 682a-682e (1938), repealed by Pub.L. No. 94-579, Title VII, § 702 (1976). The lot was leased to the Peases’ predecessor-in-interest on May 1,1953. The patent contains two relevant reservations. One is a blanket reservation for roads “constructed or to be constructed by or under authority of the United States or by any State created out of the Territory of Alaska, ...” This reservation was made pursuant to 48 U.S.C. § 321d, ch. 313, 61 Stat. 418 (1947), repealed by Pub.L. No. 86-70, § 21(d)(7), 73 Stat. 146 (1959), which provides in part:
In all patents for lands hereafter taken up, entered, or located in the Territory of Alaska, and in all deeds by the United States hereafter conveying any lands to which it may have reacquired title in said Territory not included within the limits of any organized municipality, there shall be expressed that there is reserved, from the lands described in said patent or deed, a right-of-way thereon for roads, roadways, highways, tramways, trails, bridges, and appurtenant structures constructed or to be constructed by or under the authority of the United States or of any State created out of the Territory of Alaska....
The other relevant reservation in the patent reserves a 33 foot right-of-way for roadway purposes along the south and east boundaries of the tract. Rabbit Creek Road lies on the south boundary of the Peases’ property. As this case has been presented all parties have assumed that Rabbit Creek Road was in existence as a local road at all times relevant to the various orders hereafter discussed. We make the same assumption.
In 1978 the State widened Rabbit Creek Road from 66 feet to 100 feet. The road occupied a 33 foot strip on the Peases’ property before widening and a 50 foot strip after widening. The State claimed a 50 foot easement on each side of the center line of Rabbit Creek Road, citing PLOs 6011 and 757,2 and DO 26653 as authority for widening the road without compensating the Peases for taking the extra 17 feet.
PLO 601, effective August 10,1949, withdrew “the public lands in Alaska lying within ... 150 feet on each side of the center line of all ... through roads, 100 feet on each side of the center line of all feeder roads, and 50 feet on each side of the center line of all local roads, ... from all forms of appropriation under the public land laws, ...” and reserved them “for highway purposes.” 4
The Secretary of the Interior promulgated PLO 757 and DO 2665 on October 19, 1951. 16 Fed.Reg. 10,749, 10,752 (1951). DO 2665 was filed first. Id. at 10,752. It established, among other things, easements, rather than withdrawals, of 50 feet on each [719]*719side of the center line of each local road and of 100 feet as to each feeder road.5 PLO 757 amended the sixth paragraph of PLO 601, see note 4 supra, increasing the withdrawal for the Seward Highway [the Anchorage-Potter-Indian Road in PLO 601] from 100 feet to 150 feet on each side of the center line. 16 Fed.Reg. 10,749, 10,750 (1951). PLO 757 repealed the general withdrawal for local and feeder roads contained in the sixth paragraph of PLO 601, thus effecting a revocation of the 601 withdrawals as to them. However, PLO 757 acknowledged that DO 2665 had already established easements as to feeder and local roads and did not purport to revoke them. The final paragraph of PLO 757 states: [720]*720Thus one effect of PLO 757 and DO 2665 was to substitute easements for the withdrawals made in PLO 601 as to local and feeder roads.
[719]*719Easements having been established on the lands released by this order, such lands are not open to appropriation under the public land laws....6
[720]*720The State’s claim to the full 50 feet, from the center line, of Rabbit Creek Road is in all relevant respects identical to the claim that it successfully asserted in State, Department of Highways v. Green, 586 P.2d 595 (Alaska 1978). In Green, as in the Peases’ claim, the patents were issued by the United States under the Small Tract Act and contained blanket roadway easements under 48 U.S.C. § 321d as well as specific 33 foot easements. The local road in question in both cases was built before DO 2665 was promulgated, and the lease as well as the patent was issued after promulgation of DO 2665. We held in Green that DO 2665 was issued pursuant to 48 U.S.C. § 321a, as distinct from 48 U.S.C. § 321d; that DO 2665 was applicable to patents issued under the Small Tract Act; and that
the 50 foot right-of-way established by DO 2665 was effective even though only a 33 foot right-of-way was expressed in the patent. 586 P.2d at 600-03.
The superior court reasoned that Green was not controlling because of the provisions of the Right-of-Way Act of 1966, ch. 92 S.L.A. 1966.7 Sections 2 and 3 contain the operative provisions of the Right-of-Way Act of 1966. Section 2 precludes the State from taking “privately owned property by the election or exercise of a reservation to the state acquired under [48 U.S.C. § 321d],” and section 3 provides that the Act shall not be construed to divest the State of “any right-of-way or other interest in real property which was taken by the state, before the effective date of this Act, by the election or exercise of its right to take property through a reservation acquired under [48 U.S.C. § 321d].” The effective date of the Right-of-Way Act of 1966 was April 14, 1966.
[721]*721The court erred in applying the Right-of-Way Act of 1966 to the Pease case. It is applicable only to interests taken by the State under a blanket reservation created pursuant to 48 U.S.C. § 321d. We held in Green that easements established by DO 2665 were established under the authority of section 321a, not section 321d.8 Green, 586 P.2d at 600 n. 17. Further, we held in State, Department of Highways v. Crosby, 410 P.2d 724 (Alaska 1966) that § 321d did not apply at all to patents issued under the Small Tract Act. Id. at 728.
The superior court also concluded in its Memorandum of Decision that the easement which otherwise would have been created under DO 2665 on Rabbit Creek Road did not come into being “until the right-of-way was staked by the terms of DO 2665.” This statement refers to subsection 3(c) of DO 2665, which provides:
The reservation mentioned in paragraph (a) and the rights-of-way or easements mentioned in paragraph (b) will attach as to all new construction involving public roads in Alaska when the survey stakes have been set on the ground and notices have been posted at appropriate points along the route of the new construction specifying the type and width of the roads.9
The superior court’s conclusion that the staking requirement of section 3(c) was applicable to Rabbit Creek Road is erroneous. Section 3(c) by its express terms only applies to new construction. Rabbit Creek Road was an existing road when the order was promulgated. As to existing roads, subsection 3(b) of the order establishes a 50 foot easement in the present, rather than the future, tense and contains no call for additional action in order to fix the easement. It states:
A right-of-way or easement for highway purposes covering the lands embraced in the ... local roads equal in extent to the width of such roads as established in section 2 of this order, is hereby established for such roads over and across the public lands.
16 Fed.Reg. 10,752 (1951) (emphasis added). Subsection (3) of section 2 of DO 2665 set the width of local roads at 50 feet on each side of the center line. Thus, these two sections of DO 2665 established a 50 foot easement for Rabbit Creek Road.
[722]*722The history of the promulgation of DO 2665 also demonstrates that the staking requirement applies only to new construction, not existing roads. In territorial days road easements were created across public land under 43 U.S.C. § 932, repealed by Pub.L. No. 94-579, Title VII, § 706(a) (1976), a statute remarkable for its brevity, which provided:
The right-of-way for the construction of highways over public lands, not reserved for public uses, is hereby granted.
This blanket grant had to be accepted. A common method of acceptance was the building of a road by a public authority.10 But other methods of acceptance were also recognized. As we stated in Hamerly v. Denton, 359 P.2d 121 (Alaska 1961) with respect to 43 U.S.C. § 932:
[Bjefore a highway may be created, there must be either some positive act on the part of the appropriate public authorities of the state, clearly manifesting an intention to accept a grant, or there must be public user for such a period of time and under such conditions as to prove that the grant has been accepted.
Id. at 123 (footnote omitted). In Girves v. Kenai Peninsula Borough, 536 P.2d 1221 (Alaska 1975), we held that enactment by the territorial legislature of a law dedicating a four rod strip along all section lines for roadway purposes was a positive act of acceptance of the section 932 grant. Id. at 1225-26.
When acceptance of the section 932 grant occurred by construction of a road by an appropriate public authority, a question remained regarding the width of the right-of-way thereby created. It was held that the width was not confined necessarily to the traveled portion of the roadway, but that “local laws, customs and usages” would control. City of Butte v. Mikosowitz, 39 Mont. 350, 102 P. 593, 595-96 (1909); see also Ball v. Stephens, 68 Cal.App.2d 843, 158 P.2d 207, 209 (1945).
One purpose of DO 2665 was to define as a matter of local law or usage the width of roadway easements which had been created by the construction of roads and which would be created in the future by the construction of new roads. The memorandum of February 7, 1951, from the chief counsel of the Bureau of Land Management to the Bureau’s director11 makes this clear:
Notwithstanding that section 2477 of the Revised Statutes (43 U.S.C. § 932) does not fix the width of the rights-of-way granted by it, the width when fixed by a positive act of the proper State or Territorial authorities has been held valid. Costain v. Turner (1949) [72 S.D. 427], 36 N.W.2d 382; Butte v. Mikosowitz (1909) [39 Mont. 350], 102 P. 593. In both cases, the width fixed included an area in excess of the beaten path or track. The reasons which sustain the conclusion reached in those cases support the conclusion that in the case of public highways in Alaska constructed or maintained under the jurisdiction of the Secretary of the Interior, the width of the highways may be fixed by that official.
The memo goes on to suggest the publication of an order, which was to become DO 2665, in terms which make it clear that the staking requirement only applies to new construction and not to existing roads:
The following procedure is suggested for the establishment of highway easements of prescribed widths in Alaska:
(1) The issuance of an order by the Secretary of the Interior to be published in the Federal Register fixing the width for existing roads and the width for new construction, including changes in the location of existing roads, and extensions of such roads. In the case of new construction, the order can only be effective when the survey stakes have been set on the ground.
(Emphasis added).
Further, the Superior Court’s conclusion that the staking requirement applies to ex[723]*723isting roads as well as to roads to be constructed in the future is in conflict with our holding in Green, supra. The local road in question there was constructed before the promulgation of DO 2665. As to the Green parcel, we held that the 50 foot right-of-way was fixed as of the promulgation of the order. Green, 586 P.2d at 604.
For these reasons we conclude that the State’s appeal with respect to the adverse judgment on the cross-claim of the Peases is well-founded. The third paragraph of the declaratory judgment is therefore reversed. Since the first paragraph of the judgment includes the situation presented in the Pease case, it too must be reversed.
II
THE STATE’S APPEAL AS TO BOYSEN’S PROPERTY
The discussion in this section concerns the plaintiff’s eighth claim for relief, which is reflected in the second and third paragraphs of the judgment. This discussion is also relevant to the second claim for relief relating to feeder roads. Because specific facts concerning the Hansen parcel require that it be treated differently, we exclude it from this discussion and focus instead on the Boysen property.
This aspect of the case involves an additional public land order that was not involved in the discussion of the Pease case. This order, PLO 1613, was promulgated April 7, 1958. 23 Fed.Reg. 2376, 2378 (1958). PLO 1613 revoked PLO 601 which, as modified by PLO 757, had withdrawn and reserved for highway purposes 150 feet on each side of the Seward Highway. Id. at 2376. PLO 1613 converted the 150 foot Seward Highway right-of-way to an easement of the same width.12
The Boysen parcel consists of some 80 acres joining the Seward Highway. The patent was issued to Boysen’s predecessor on May 15, 1952, under the Homestead Act. The homestead entry was made January 2, 1951. The patent contains a blanket reservation for road rights-of-way as required by 48 U.S.C. § 321d. See page 718 supra.
Setting aside the possible effect of the section 321d reservation, the homestead entry of Boysen’s predecessor in January 1951 fixes the date from which the property rights of the owners of the parcel are to be measured.13 As of that date, PLO 601 had withdrawn 100 feet of land from each side of the center line of the Seward Highway. 14 Fed.Reg. 5048 (1949).
The superior court was apparently of the view that unless the State had fully occupied or staked this 100 feet before the effective date of the Right-of-Way Act of 1966, that act eliminated the withdrawal. We disagree.
The Seward Highway was in existence by the time of the homestead entry. The superior court apparently imposed the staking requirement because of section 3 of DO 2665.14 For the reasons we have expressed with respect to the Peases’ property, the superior court’s conclusion concerning the applicability of the staking require[724]*724ment to the Seward Highway is erroneous. The Seward Highway was not new construction in 1949, when PLO 601 was promulgated, or in 1951, when DO 2665 was promulgated. It had a fixed location and the boundaries of its right-of-way were ascertainable by referring to the applicable PLO and measuring from its center line.
In addition, the 100 foot right-of-way first created by PLO 601 does not depend for its existence on the reservation placed in the patent under section 321d. PLO 601 was issued pursuant to Executive Order 9337, 8 Fed.Reg. 5516 (1943), under which the President of the United States delegated his authority to the Secretary of the Interior under 43 U.S.C. § 141, ch. 421, § 1, 36 Stat. 847 (1910), repealed by Pub.L. No. 94-579, Title VII, § 704(a) (1976), authorizing withdrawal of public lands in Alaska for specified public purposes.15 As previously noted, the Right-of-Way Act of 1966 applies only to rights-of-way acquired under section 321d reservations.
For the above reasons the second paragraph of the judgment as it relates to the Boysen property must be reversed. The preceding discussion also requires, as did our discussion in part I concerning the Peases’ property, reversal of the first paragraph of the judgment. We do not reach the question whether a full 150 foot easement became fixed across the Boysen property by operation of the section 321d patent reservation and promulgation of PLO 757, and thus may be unaffected by the Right-of-Way Act of 1966. This question was not specifically addressed by the superior court nor is it presented in the briefs before us.
Ill
THE CROSS-APPEAL AS TO THE HANSEN PROPERTY
The patent for the Hansen parcel was issued to Hansen’s predecessor-in-interest on June 1, 1950, under the Homestead Act. The homestead entry was made on January 23, 1945, before the promulgation of any of the land orders previously discussed, and before passage of 48 U.S.C. § 321d. The patent to the Hansen property does not contain a section 321d reservation.
The PLO 601 withdrawal was expressly subject to “valid existing rights.” 14 Fed. Reg. 5048 (1949). Homestead entries have been held to give rise to valid existing rights,16 although those rights may not in all cases take priority over intervening government acts.17 Here, however, there is no doubt of the intention to except prior homestead entries from PLO 601. As we have noted, PLO 601 was promulgated pursuant to 43 U.S.C. § 141. 43 U.S.C. § 142 states that “there shall be excepted from the force and effect of any withdrawal made under the provisions of ... section 141 ... all lands which are, on the date of such withdrawal, embraced in any lawful homestead ... entry .... ” Since entry was in 1945, and the first withdrawal occurred in 1949, Hansen’s predecessor-in-interest, as an entryman, had rights superior to the withdrawals.
Section 321d has no effect on the Hansen property. The mandatory reservation required by this statute was limited to “patents for lands hereafter taken up, entered, or located in the Territory of Alaska, ...” (emphasis added). Since the Hansen land was entered in 1945, it was not “hereafter” entered and thus was excluded from the operation of that statute. This is consistent with the absence of the section 321d reservation in the Hansen patent, and also consistent with its presence in the patents to the other two parcels of land involved in this appeal where entry occurred after July [725]*72524,1947, the date on which section 321d was adopted.
Thus, for reasons different from those articulated by the superior court, the second paragraph of the declaratory judgment is affirmed as to the Hansen parcel.
IV
TRANSAMERICA’S LIABILITY
In count I of the complaint, Trans-america sought a declaration absolving it of liability to the Peases under its title insurance policy. The superior court, following Hahn v. Alaska Title Guaranty Co., 557 P.2d 143 (Alaska 1976), found Transamerica conditionally liable to the Peases for the value of the 17 foot strip arising from DO 2665. In Hahn we held that the publication of a public land order, there PLO 601, in the Federal Register imparted constructive notice of the order as to the land it effected. Under the terms of the title policy there involved, the title insurance company was found to be liable. Id. at 146. We agree that Hahn is squarely controlling.
Transamerica, however, contends that Hahn should be overruled. We have considered Transamerica’s arguments in support of this position and we are not persuaded that Hahn is unsound in any respect. We therefore decline to overrule it. Thus, Transamerica is liable under its policy to the Peases. Paragraph 4 of the declaratory judgment so far as it relates to Transameri-ca’s liability to the Peases is affirmed.
V
CROSS-APPEAL AS TO FIFTH, SIXTH, SEVENTH AND NINTH CLAIMS FOR RELIEF
The plaintiffs claim that the superior court should have granted summary judgment in their favor on their fifth, sixth, seventh and ninth claims for relief. The court made no ruling as to these claims. We review them in accordance with the principle that any ground may be urged on appeal to support a judgment even if it was not accepted by the court in rendering judgment. Moore v. State, 553 P.2d 8, 21 (Alaska 1976); Ransom v. Haner, 362 P.2d 282, 285 (Alaska 1961).
The fifth and sixth claims are similar because to prevail, a property owner18 must establish status as a “subsequent innocent purchaser ... in good faith for a valuable consideration” as that term is used in AS 34.15.290. An innocent purchaser must lack “actual or constructive knowledge” of the conflicting deed or encumbrance that the purchaser seeks to avoid. Sabo v. Horvath, 559 P.2d 1038, 1043 (Alaska 1976). Sabo held that as between two grantees, a pre-patent grantee’s deed that was recorded before the patent was issued is a “wild deed” and does not give constructive notice to a post-patent grantee who duly records. Id. at 1044.
The question here is whether public land orders, which appear in the Federal Register, impart constructive notice, thus preventing the property owner from claiming innocent purchaser status. We have in part IV of this opinion re-affirmed the holding of Hahn v. Alaska Title Guarantee Co., 557 P.2d 143 (Alaska 1976) that publication of a land order in the Federal Register is constructive notice of the order as that, term is used in a title insurance policy. That holding is controlling here.
The distinction between Sabo and this appeal is that Sabo concerns private deeds and this appeal involves a conflict between a government regulation and a patent. Regulations published in the Federal Register take on the character of law. Farmer v. Philadelphia Electric Co., 329 F.2d 3, 7 (3d Cir.1964); United States v. Messer Oil Corp., 391 F.Supp. 557, 561-62 (W.D.Pa.1975). All persons are presumed to know the contents of the law. See Ferrell v. Baxter, 484 P.2d 250, 265 (Alaska 1971). In United States v. Messer Oil Corp., the district court indicated that regu[726]*726lations published in the Federal Register were sufficient notice to allow conviction of a criminal violation. 391 F.Supp. at 562. If Federal Register notice is sufficient for this purpose, it is sufficient notice to a landowner regarding easements that the federal government has reserved across his land. Thus, the publication of the land orders in the Federal Register imparted constructive notice and served to preclude subsequent innocent purchaser status.
In the seventh claim, plaintiffs contend that the State is estopped from claiming any easements under the orders here involved. The State responds that constructive notice defeats the estoppel claim.
Estoppel requires “the assertion of a position by conduct or word, reasonable reliance thereon by another party, and resulting prejudice.” Jamison v. Consolidated Utilities, Inc., 576 P.2d 97, 102 (Alaska 1978) (footnote omitted). Plaintiffs claim that the State has asserted by conduct that it claims no easements by allowing the owners to develop their property inconsistently with the easements, and by not recording the land orders. They assert that reasonable reliance on that assertion has taken place. Because we have already found that publication of the land orders imparts constructive notice of the easements which they create, that notice makes plaintiffs’ reliance unreasonable. Thus, the estoppel claim lacks merit.
The ninth claim of plaintiffs is based on the fact that the property owners’ patents involved here did not expressly refer to any land order easements. Because of this the plaintiffs contend that the property conveyed was conveyed free from such easements. They argue further that as a result suit was required to be brought against the property owners to vacate the patents, and that the time for such a suit is, in all cases now before us, barred by the six year statute of limitations contained in 43 U.S.C. § 1166.19
The premise of this argument is that a patent which does not say that it is issued subject to a public easement operates to transfer the property free from the easement. We rejected this premise in Green. We held there that an unexpressed DO 2665 easement was effective. Green, 586 P.2d at 603.
Similarly, in Girves v. Kenai Peninsula Borough, 536 P.2d 1221 (Alaska 1975), we affirmed a trial court ruling that a right-of-way not expressed in a patent was effective:
At the outset Girves notes that neither her “Notice of Allowance”, nor her patent contained any express reservation of rights-of-way in favor of any public body. However, the absence of an express reservation of easement does, not preclude the borough from showing that a right-of-way was established prior to the issuance of these documents.
Id. at 1224 (footnote omitted). We cited as authority for that statement State v. Crawford, 7 Ariz.App. 551, 441 P.2d 586 (1968). That case aptly states:
[I]t is also clear from cases decided under 43 U.S.C. § 932 that a subsequent pat-entee takes subject to previous right-of-ways [sic] established under the grant contained in that federal statute [Citations omitted.] No contrary authority has come to our attention.... The silence of the patents does not preclude the State from showing the full extent of its right-of-way established prior to the time when the patents were issued to plaintiff’s predecessors.
Id. at 590.
The above and other authorities20 establish that, by operation of law, [727]*727land conveyed by the United States is taken subject to previously established rights-of-way where the instrument of conveyance is silent as to the existence of such rights-of-way. No suit to vacate or annul a patent in order to establish a previously existing right-of-way is necessary because the patent contains an implied-by-law condition that it is subject to such a right-of-way.21 Thus the statute of limitations expressed by 43 U.S.C. § 1166 does not apply.
VI
CONCLUSION
The first paragraph of the judgment is REVERSED. The second paragraph of the judgment is AFFIRMED as to Hansen and REVERSED as to Boysen. The third paragraph of the judgment is REVERSED. The fourth paragraph of the judgment is AFFIRMED as to the Peases’ claim against Transamerica. The case is REMANDED for further proceedings consistent with the foregoing.