Doris Slaaten appeals from the district court’s dismissal of her suit against the United States for conversion of oil and gas royalty payments. The district court held that Slaaten’s suit was barred by the Federal Tort Claims Act two-year statute of limitations. 28 U.S.C.A. § 2401(b) (Supp. 1992). Slaaten argues that she complied with the two-year statute of limitations because her claim did not accrue until September 19, 1989, when an Interior Board of Land Appeals decision, reversing a longstanding government position and holding that the United States had no claim to the royalties, became final. We conclude that Slaaten complied with the two-year statute of limitations. Accordingly, we reverse and remand for further proceedings.
On May 25, 1937, Doris Slaaten’s parents conveyed 160 acres located in North Dakota to the United States. The deed contained a mineral reservation in favor of the Slaatens, limited to twenty-five years with the option to extend the reservation. The deed also provided that the reservation would expire on November 4, 1961, and that any extension of the mineral rights would be limited to an area of twenty-five acres of land surrounding each well or mine that was producing at the time the right terminated.
In 1948, Maude Slaaten, Doris Slaaten’s mother, leased the mineral interest to Thomas Dorough, who assigned the lease to Texaco. Texaco constructed two oil and gas wells on the property. In August 1961, Texaco and the United States interpreted the mineral reservation right in the deed to mean that the United States owned the mineral interest in all but the twenty-five acres of property surrounding each of the two existing wells. Accordingly, Texaco reduced Slaaten’s royalties and entered into a compensatory royalty agreement with the United States, giving the government a portion of the royalties.
In 1967, a North Dakota district court held that the mineral reservation languagé in a deed identical to Slaaten’s resulted in a relinquishment of the ownership of the mineral rights, except for twenty-five acres surrounding each producing well. 1 United *1040 States v. Amax Petroleum Corp., Civil No. 712 (D.N.D. Oct. 16, 1967). Although the decision was unpublished and Slaaten was not a party to the suit, the court’s interpretation supported the United States’ position that it owned the mineral rights in all but the twenty-five acres surrounding each well. In 1968, Maude Slaaten wrote the Bureau, objecting to the compensatory royalty agreement and contending that she had repeatedly refused to recognize the government’s claimed interest. The Bureau responded that the United States was entitled to payment under the Texaco royalty agreement and suggested that the question of the royalties Texaco owed to Slaa-ten was a private lease matter that she should negotiate with Texaco.
In 1985, the United States entered into an agreement with the Amerada Hess Corporation, authorizing Amerada Hess to develop the remaining 110 acres of land for oil and gas production. Amerada Hess paid the United States a bonus of $1,251,-836 for the drilling and production rights. Amerada Hess completed an oil and gas well in 1985 and has paid royalties to the United States since that time.
On December 5, 1986, Doris Slaaten 2 filed a letter of protest with the Bureau, disputing the United State’s interest in the minerals. In support of her protest, she attached an engineer’s analysis 3 of her rights. In January 1987 the Bureau dismissed her protest. The Bureau explained that “[i]t has been the Bureau’s position, in response to numerous questions about these 25-acre reservations, the government acquired the entire present interest to the mineral estate in the lands covered by the respective deeds, excepting 25 acres surrounding (around) each producing well being drilled or developed at the end of the reservation period.” The Bureau also stated that “[t]his position, we believe, was upheld by Judge Register’s judgment” in Amax. The Bureau then advised Slaaten that she could appeal to the Interior Board of Land Appeals, and she filed a notice of appeal on February 11, 1987. On January 25, 1989, the Board issued a decision rejecting the Bureau's position and Amax, even though it recognized that the Bureau had “long interpreted” such restrictions in favor of the United States. Doris Slaaten, 107 IBLA 16, 20, 23 (1989). The Board concluded that the United States never had a right to the minerals. 4 Id. at 25. The Board denied the Bureau’s petition for reconsideration on September 19, 1989, and the Bureau did not appeal the decision further.
Slaaten then presented a claim for $1,764,941.10 to the Bureau on April 17, 1990, claiming that the United States had negligently and wrongfully converted her property to its own use since November 1961. Because the Bureau did not respond within six months, she filed this action with the district court in March 1991.
The government requested summary judgment, which the district court granted with “great reluctance” because it believed the Federal Tort Claims Act two-year statute of limitations applied and barred consideration of Slaaten’s claim. Slaaten v. United States, No. A4-91-038, slip op. at 8 (D.N.D. Jan. 2, 1992). The district court found that Slaaten had the requisite knowledge of her claim on December 5, 1986, but failed to file a claim for a sum certain until April 17, 1990. Id. The court also ruled that no equitable considerations were present to toll the statute of limitations. Id. The court noted that its reluctance was:
*1041 predicated upon the fact that the plaintiff and her family appear to have been victimized by the government ... for many years, and even after winning a favorable result in the administrative process, were told that a judicial decree was necessary to obtain relief. When seeking such a judicial decree they are met with great objection.
Id.
We review the district court’s grant of summary judgment de novo, and will affirm only “when there is no genuine issue as to any material fact and ... the moving party is entitled to judgment as a matter of law.” Fed.R.Civ.P. 56(c);
McKee v. Federal Kemper Life Assur. Co.,
Section 2401(b) of the Federal Tort Claims Act requires that claimants present a claim to an appropriate federal agency within two years after the claim accrues and file an action within six months of the agency’s certified or registered mailing of a claim’s final denial. 28 U.S.C.A. § 2401(b). In addition, the presented claim must be for a sum certain in damages. 28 C.F.R. § 14.2(a) (1992);
Melo v. United States,
A claim “accrues” when the plaintiff knows or reasonably should know both the existence and cause of the injury.
United States v. Kubrick,
Slaaten contends that her claim did not accrue until September 19, 1989, when the Board’s decision, rejecting
Amax
and determining that the United States did not have an interest in the oil and gas, became final. Relying on our decisions in
United States v. LePatourel,
In
LePatourel,
a federal judge, driving on official business, was involved in a car accident which injured Valerie LePatourel.
When
LePatourel I
came before this court, we reversed the district court and held (for the first time) that the FTCA applied to federal judges.
Id.
at 410. We also held, however, that the FTCA two-year statute of limitations barred the LePatour-els’ claims.
Id.
On petition for rehearing, we considered whether our holding should be applied prospectively, and remanded the case to the district court to determine why the LePatourels had failed to file within the two-year period.
Id.
at 410-11. After the district court held that the LePatourels should be allowed to proceed with their claims, we affirmed en banc, holding that the statute of limitations did not begin to run until our panel determined that the
*1042
FTCA applied to federal judges acting in the scope of their employment.
LePatourel II,
Similarly, on this record, it cannot be said that Slaaten had knowledge of her injury before September 19, 1989, when the Board rejected the Bureau’s long-held position and
Amax.
All indications before that time were that Slaaten had no injury. Indeed, the Bureau had stated that it had taken the position that the government was entitled to the entire mineral estate except the twenty-five acres surrounding each producing well “in response to numerous questions about these 25-acre reservations.” The Board’s decision, rejecting
Amax
and the Bureau’s long-held position, therefore, was “ ‘an avulsive change which caused the current of the law thereafter to flow between new banks.’ ”
LePatourel II,
The government, however, argues that Slaaten knew the government had injured her by at least December 5, 1986. In other words, her claim accrued under
Kubrick,
In
Kubrick,
Here, however, we are dealing with property rights. Slaaten’s knowledge of her injury (as described by the district court, the government’s wrongful exercise of control over her property) was dependent upon the legal determination of whether the government’s conduct was wrongful. Without the wrongful exercise of control, Slaaten has not suffered an injury.
Cf. Kubrick,
Although the government urges us to affirm the district court, it also takes exception to the court’s finding that Slaaten had the requisite knowledge of her claim on December 5, 1986. The government argues that Slaaten’s claim accrued in 1961 because Maude Slaaten, Doris Slaaten’s predecessor in interest, had knowledge of the fact of injury or its cause in 1961 when the United States entered into the compensatory agreement with Texaco. In accordance with our holding, we reject this argument. On this record, we cannot say that either Maude or Doris Slaaten knew of the injury (the government’s wrongful exercise of control over the property) before the Board’s decision became final. 5
The government also argues that unlike
LePatourel I,
which was a published decision from this court,
Amax
was an unpublished district court decision which did not have precedential value and could not have barred Slaaten’s claim in district court. The government has cited our rules and cases in which we refuse to recognize unpublished opinions as precedent.
See, e.g.,
Eighth Cir.R. 28A(k). A procedural rule in the workings of our court, however, is not determinative of the controversy between Slaaten and the government. Even though
Amax
was not published, it was the basis for the Bureau’s position in this case and the Bureau’s responses to “numerous questions about these 25-acre reservations.” Thus, in reality,
Amax
had precedential effect on the Bureau. Therefore, this is similar to the situation in
LePatourel
in which the predominant understanding of the law had been in one direction, and later changed to go in the opposite direction.
See LePatourel II,
The government also contends that extending
LePatourel II
to this case would essentially eliminate the FTCA statute of limitations. We rejected a similar argument in
LePatourel II,
because “the class of claimants similarly situated ... cannot be so large as to threaten the interests protected by § 2401(b).”
Although the government raises various other arguments, we need not address them as we have concluded that Slaaten did *1044 not have the requisite knowledge of her injury (the statute of limitations did not begin to run) until the Board’s decision became final. The FTCA statute of limitations does not bar Slaaten’s claim. We reverse and remand for further proceedings.
Notes
. Specifically, the court held that when the reservation expired, all minerals in the lands were vested in the United States, except for twenty-five acres of land around each producing well *1040 which remained with the defendants. Slip op. at 3.
. Maude Slaaten conveyed all her interest to Doris Slaaten sometime before December 5, 1986.
. The engineer concluded that the deed's twenty-five acre provision could not limit Slaaten’s interest because all 160 acres of land had been fully developed with two 80-acre oil producing units, and therefore, Slaaten maintained her interest in all 160 acres.
. The Board did not adopt either Slaaten's or the Bureau's position. Instead, the Board ruled that once the deed’s condition precedent was met in some way (the requirement of producing for a commercial advantage), the exclusive right to prospect in, under, and upon the entire piece of land was automatically extended and remained with Slaaten. 107 IBLA at 23.
. Contrary to assertions by the parties and the district court, section 2401(b)’s limitation period is not jurisdictional in nature.
See Irwin v. Veterans Admin.,
