Read the following excerpt from a US court opinion:
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theory that the district court rejected before. Gore does not point to any change in the relevant law. This is also not a case in which the district court made findings on remand th nts, or any interest therein, shall be assignable by law in an instrument in writing.”) (emphases added). However, BPV has never claimed that in 2003 it had all substantial rights to the '135 patent. BPV’s position is only that it was an exclusive licensee with the right to sue for infringement. It is well established that the grant of a license does not need to be in writing. See Waymark Corp. v. Porta Sys. Corp., 334 F.3d 1358, 1364 (Fed.Cir.2003) (“Only assignments need be in writing under 35 U.S.C. § 261. Licenses may be oral.”); Rite-Hite Corp. v. Kelley Co., 56 F.3d 1538, 1552 (Fed.Cir.1995) (en banc) . In any event, in 1997 there was a
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What is the most suitable continuation to the opinion? Your options are:
A. holding that to be an exclusive licensee a party may rely on either an express or implied promise of exclusivity
B. holding that a contract for an exclusive agency to market a product contains an implied promise to use all reasonable efforts to market the product
C. holding that the other source of law might be a moneymandating constitutional provision statute or regulation that has been violated or an express or implied contract with the united states
D. holding that an implied contract may not be found if there is an express contract between the same parties on the same subject matter quoting 42 cjs implied and constructive contracts  34 p 33
E. holding that a promise to make a loan is not covered by  1823e because a promise is not an asset
Reply with [A, B, C, D, E] only.