dissenting.

The majority opinion thoughtfully examines the issues involved in determining what constitutes a sale for experimental purposes under 35 U.S.C. § 102 (b). 1 The opinion, however, overlooks decisive inferences and case law and frustrates an independent inventor’s ability to market his invention, and reap the rewards of his creativity. Therefore, I respectfully dissent.

This case is here on appeal from the district court’s order granting summary judgment for the defendants. Thus, the primary question before us is whether, after construing all evidence in the light most favorable to plaintiff, the non-moving party, there remains a material question of fact whether the sale of the prototype was for an experimental purpose. Fed.R.Civ. Pro. 56(c); Pegasus Fund, Inc. v. Laraneta, 617 F.2d 1335, 1339 (9th Cir. 1980). Since material questions of fact exist, we should remand for trial.

Our court has stated that resolution of the question whether a sale had an experimental purpose depends upon “the totality of evidence presented by both parties, of the nature of the acts committed prior to the critical date and the purpose that motivated the commission of those acts.” Cataphote Corporation v. DeSoto Chemical Coatings, Inc., 356 F.2d 24, 26 (9th Cir.), modified on other grounds and reh’g denied, 358 F.2d 732 , cert. denied, 385 U.S. 832 , 87 S.Ct. 71 , 17 L.Ed.2d 67 (1966). In analyzing the “totality of evidence” a number of factors should be examined to determine whether a sale had an experimental, not a commercial, purpose. These factors include: conditions placed on the sale, Robbins v. Lawrence, 482 F.2d 426, 432 (9th Cir. 1973); further testing required on the product, Amerio Contact Plate Freezers, Inc. v. Belt-Ice Corp., 316 F.2d 459, 464 (9th Cir.), cert. denied, 375 U.S. 902 , 84 S.Ct. 191 , 11 L. Ed.2d 143 (1963), Timely Products Corp. v. Arron, 523 F.2d 288, 302 (2d Cir. 1975); explicit statements of an experimental purpose, Austin Machinery Co. v. Buckeye Traction Ditcher Co., 13 F.2d 697, 700 (6th Cir. 1926), cert. denied, 273 U.S. 747 , 47 S.Ct. 448 , 71 L.Ed. 871 (1927), Robbins, 482 F.2d at 433 ; inventor’s intent that transfer be for an experimental purpose, In Re Yarn Processing Patent Validity Litigation, 498 F.2d 271, 288 (5th Cir.), cert. denied sub nom. Sauquoit Fibers Co. v. Leesona Corp., 419 U.S. 1057 , 95 S.Ct. 640 , 42 L.Ed.2d 654 (1974); requirement that invention be kept confidential, Ajem Laboratories, Inc. v. C. M. Ladd, 424 F.2d 1124 , 1125-26 (6th Cir.), cert. denied, 400 U.S. 830 , 91 S.Ct. 59 , 27 L.Ed.2d 60 (1970), Robbins, 482 F.2d at 432 ; further experimentation on the invention, Del Mar Engineering v. Physio-Tronics, 642 F.2d 1167, 1169 (9th Cir. 1981); commercial motive incidental to the experimental motive, In Re Yarn Processing Patent Validity, 498 F.2d at 277-78 , Pickering v. Holman, 459 F.2d 403 (9th Cir. 1972); and reports to the inventor on transferee’s use of the invention, Robbins, 482 F.2d at 433 .

A number of these factors exist in this case. The April 28th agreement required Merry to notify Kock of all design changes and secure his approval of the patent application. Since reports to the inventor on the use of the invention by the transferee indicate a transfer for an experimental purpose, Robbins, 482 F.2d at 433 , the notifica *660 tion requirement raises an inference that Kock and Merry intended the experimental process to continue. 2

The transfer here required secrecy in the use of the device — another indicator of an experimental purpose. Robbins, 482 F.2d at 433 . Kock swore in an affidavit that he and Merry agreed to keep the newly invented watch secret. There is no evidence that Kock revealed the workings of his invention to anyone other than his patent attorney and Merry, with whom he had an exclusive contract. Again, the evidence raises an inference that the transfer was for an experimental purpose.

A sale from an inventor to a manufacturer before the product has been “tested sufficiently to verify that it is operable and commercially marketable” raises an inference of an experimental purpose. Timely Products Corp. v. Arron, 523 F.2d at 302 . For example, in Amerio Contact Plate Freezers v. Belt-Ice Co., 316 F.2d at 465 , this court held that selling activity does not activate section 102(b)’s one year period until an operative “prototype has been completed and tested,” because such activity may be necessary to ascertain what product changes are required for successful commercial exploitation. The April 28th agreement contained a provision that Merry had ninety days to test the product and decide whether to produce it commercially. The agreement also required Kock to provide additional prototypes, if requested. This evidence raises the inference that, as of April 28, Kock’s invention had not been sufficiently completed and tested to verify that it was operable and commercially marketable. This inference places the sale within the experimental purpose exception to section 102(b).

The majority acknowledges that section 102(b) does not apply “to a sale to improve or perfect the invention. . . . where the profit motive is only incidental to the experimental .... ” Majority Opinion at 654. The majority, however, fails to apply this rule to the facts of this case. Here, as discussed in the previous paragraph, the inference can be drawn that the purpose of the transfer was to improve or perfect the invention. Kock, after three months of work, transferred a prototype embodying his invention to Merry for an initial payment of $1,500. Under the contract, Kock was also to receive $1,000 for each additional prototype he was asked to produce. Moreover, he was to receive a three percent royalty based on the net selling price of all watches produced pursuant to the invention. The initial payment was minor compared to the eventual profits Kock hoped to reap. Thus, one might infer that Kock’s profit motive, exhibited when he accepted $1,500 for three months work, was incidental to his experimental motive — that the invention be improved or perfected through the use of Merry’s superior facilities. Again, one may draw the inference that the transfer was for an experimental purpose.

The majority opinion overlooks the inferences discussed in the preceding paragraphs. 3 Nonetheless, it concedes that

Majority Opinion at 660-661.

This acknowledgment of a triable issue of fact as to the experimental purpose of the April 28th transaction should by itself require a remand.

There is also a question of fact whether the April 28th transfer was a transaction between an inventor and a third party within the product’s production or distribution system. Such transfers, which reflect an experimental rather than a commercial purpose, do not constitute sales under section 102(b). 4

The evidence suggests the April 28th transaction could have constituted a transfer within a production and distribution system. Kock began working on the invention after Merry sent Kock a letter, dated September 15, 1966, which detailed the watch movement Merry desired. Thus, the invention was built exclusively for Merry to meet its specific requirements. Since Kock maintained a royalty interest, most of his remuneration would derive from Merry’s marketing of the ultimate product, not the initial $1,500 payment. As the majority notes, the worth of the product could have depended on the “use of Merry’s superior testing facilities.” Majority Opinion at 658. The contract called for Kock to continue to work as a consultant for Merry. Neither Kock nor Merry disclosed the invention to anyone other than Kock’s patent attorney. The evidence recited above raises a strong inference that Kock and Merry constituted a production entity, a subject the majority fails to address. 5

The majority opinion also ignores the policy behind section 102(b). As Robbins noted: “The underlying policy [of section 102(b) ] appears to be that an unconditional placing ‘on sale’ creates an opportunity for public use.” (Emphasis in the original.) 482 F.2d at 431 . Here, the “sale” simply did not create an opportunity of public use. Thus, under Robbins , there should be no sale within the meaning of section 102(b).

Further, applying the on sale bar to this case does not advance the purpose of sec *662 tion 102(b) — that is, “to prevent an inventor from having the advantage of a monopoly for more than the statutory period by engaging in the competitive exploitation of his invention.” Amerio Contact Plate Freezers, Inc. v. Belt-Ice Corporation, 316 F.2d at 465 ; see also Pickering v. Holman, 459 F.2d at 406 ; Note, New Guidelines for Applying the On Sale Bar to Patentability, 24 Stan.L.Rev. 730, 734 (1972). Here the inventor was not attempting to prolong his monopoly but was trying to prepare the product for commercial exploitation. The purpose of section 102(b) is not served by applying the on sale bar to the sale of a single prototype produced under an exclusive contract with a production company. Cf. Cali v. Eastern Airlines, 442 F.2d 65, 69 (2d Cir. 1971). Here, the commercial exploitation contemplated by section 102(b) would have occurred when Merry marketed the completed watches. Compare American Machine & Hydraulics, Inc. v. Mercer, 585 F.2d 404 (9th Cir. 1978) (on sale bar applies to sale of 147 mufflers to ultimate customers); Robbins, 482 F.2d at 428 (on sale bar applies to sale of 50 cutters to the ultimate customer); Super Mold Corp. v. Clapp’s Equip. Div. Inc., 397 F.2d 932 (9th Cir. 1968) (on sale bar applies to sale of 248 tread aligners to the ultimate customer).

The majority opinion disregards the inferences of an experimental purpose raised by the evidence, disregards its own acknowledgment that a triable issue of fact exists, disregards the question whether the sale constituted a transfer within a production company, and disregards the policy and purpose of section 102(b). Instead, the majority concludes that defendants are entitled to summary judgment because “there is no basis for finding that Merry was required to perform further experimentation,” the inventor “waived all control over the future course of the invention,” and “Merry had the right of immediate exploitation.” Majority Opinion at 658. The majority also seems to create an apparent per se rule for determining whether a sale has an experimental purpose. The majority states

Majority Opinion at 655. This rule has scant support in past decisions. 6

*663 As I read the majority opinion, its holding is apparently based on the proposition that Kock’s transfer of “all control” over the invention constitutes a sale under section 102(b). The degree of control relinquished by an inventor through a sale does bear on whether the sale had an experimental or commercial purpose. Relinquishment of control, however, should not, as the majority believes, be a conclusive indicator of a commercial purpose. The majority does envision situations where giving up all control might not compel application of the on sale bar. The majority states that a transfer to a buyer might not come within section 102(b)

Majority Opinion at 655-656, n.8. While the inventor in the majority’s hypothetical would receive prior notification of a sale, which was more than Kock was entitled to, the hypothetical inventor would, in reality, have no greater control over the commercial exploitation of his invention than did Kock. Therefore, the majority’s concession that its hypothetical inventor may avoid the on sale bar should apply equally to Kock.

One can also envision a situation in which an inventor with a partially completed prototype is forced by lack of funds to sell his invention to a production company. The company might not wish to devote its resources to complete the prototype or produce the product that embodies the invention, unless the company has the unqualified right to control marketing of the product. Granting such control should not terminate the experimental process. The production company should have the right to continue experimenting with the product, even if such experimentation takes longer than a year. Under the majority’s view, however, to obtain a valid patent, an application must be filed within one year of the transfer of control.

The overriding consideration in applying section 102(b) to a sale is whether the sale had an experimental or commercial purpose. I suggest that the fact-finder treat transfer of control as a factor, not as a conclusive indicator of a sale within section 102(b). Courts should apply section 102(b) to invalidate a patent when the transfer of control over the invention, considered as part of the totality of the evidence, indicates the sale was for a commercial purpose. Treating transfer of control as a factor, rather than as a conclusive indicator of a sale, encourages continuation of the experimental process without fear of running afoul of section 102(b)’s one year period.

In short, the evidence in this ease raises a material question of fact whether the April *664 28th transaction was primarily for experimental or commercial purposes. Our court has held that the question of experimental purpose in cases involving section 102(b) is a question of fact to be decided by the trier of fact after consideration of the totality of the evidence. Cataphote Corporation v. De-Soto Chemical Coatings, Inc., 356 F.2d at 26 ; Micro-Magnetic, Inc. v. Advanced Auto Sales Co., Inc., 488 F.2d 771, 773 (9th Cir. 1973). See also, 2 Deller’s Walker on Patents, 714. I would therefore reverse the summary judgment and remand for trial.

. I agree with the majority’s views that experimentation may occur even if no change in the invention proves necessary, Majority Opinion at 654, and that Robbins v. Lawrence, 482 F.2d 426 (9th Cir. 1973), allows evidence of experimental purpose beyond that contained in the written contract. Majority Opinion at 657.

. The majority, however, suggests these reports were submitted only for Kock’s information and have no bearing on whether the transfer was for an experimental purpose. Majority Opinion at 657. One could also interpret this requirement as implying that the parties intended to continue experimentation while giving Merry the final authority over all design changes. In a motion for summary judgment, conflicting inferences should not be resolved in favor of the moving party as the majority has done. Pegasus Fund Inc. v. Laraneto, 617 F.2d, 1335, 1339 (9th Cir. 1980).

. Not only does the majority fail to draw inferences in favor of Kock, it draws them against him. It writes that “[t]he contract contains provisions which encourage the inference that the invention was patentable and complete at the time of sale, and hence there is no experimental purpose explaining the transfer.” Majority Opinion at 656. Inferences favoring the defendants which are “encouraged” by the evidence are irrelevant to this court’s review of a summary judgment decision favoring the defendants since “all doubt must be resolved in favor of the party opposing the motion for summary judgment.” Cermetek, Inc. v. Butler Avpak, Inc., 573 F.2d 1370, 1377 (9th Cir. 1978); see also Pegasus, 617 F.2d at 1339 .

. For example, in Baker-Commack Hosiery Mills Inc. v. Davis Co., 181 F.2d 550 (4th Cir.), cert. denied, 340 U.S. 824 , 71 S.Ct. 58 , 95 L.Ed. 605 (1950), the Fourth Circuit upheld the patent after such a transfer because “there was no sale within the terms of the statute, but only certain preliminary steps looking toward sales which in fact never occurred.” Id. at 558. In Jack Winter, Inc. v. Koratran Company, Inc., 375 F.Supp. 1 (N.D.Cal.1974), supp. op., 409 F.Supp. 1019 (1976), the court upheld a patent when the “sale” was within the “patentee’s own distribution system.” Id. at 37. See also Marvin Glass & Associates v. Sears, Roebuck & Co., 318 F.Supp 1089 (S.D.Tex.1970), aff’d in part, remanded in part on other grounds, 448 F.2d 60 (5th Cir. 1974); Note, New Guidelines for Applying the On Sale Bar to Patentability, 24 Stan.L.Rev. 730, 745 (1972).

. The majority opinion does, however, conclude that “[tjhis is not a case where the inventor entered into a joint venture.” Majority Opinion n.8, at 658. Thus, the majority apparently believes that transfers within a joint venture do not constitute a sale under section 102(b). The majority’s observation is perplexing. First, it does not explain why transfers within a joint venture should be immune from the on sale bar, while transfers within a production system should be subject to the on sale bar. Second, the basis for the majority’s belief that the agreement between Kock and Merry did not constitute a joint venture is that “the buyer here would eventually make commercial use of the invention.” Id. It is not clear why future commercial exploitation is relevant to whether a sale for commercial purposes had already occurred. Furthermore, Kock, through the receipt of royalties, anticipated that he would “eventually make commercial use of the invention” concurrently with Merry — thus, Merry’s anticipated commercial exploitation should not indicate the April 28th transaction was a transfer outside a production entity.

. The legal authority for these holdings is unclear. The majority supports its position by stating that “if the invention is out of the inventor’s hands, it is irrelevant what experiments the buyer does or does not do with the invention.” Majority Opinion at 9. The following cases relied on by the majority, however, do not support this position.

In Tool Research and Engineering Corp. v. Honcor Corp., 367 F.2d 449, 453 (9th Cir. 1966), cert. denied, 387 U.S. 919 , 87 S.Ct. 2032 , 18 L.Ed.2d 972 (1967), our court merely noted that the inventor put no limitation on his product’s use. We held the patent invalid because the sales put the invention into public use. Id. at 453. No such public use existed in the instant case.

In Dart Industries, Inc. v. E. I. DuPont DeNemours & Co., 489 F.2d 1359, 1366-67 (7th Cir. 1973), cert. denied, 417 U.S. 933 , 94 S.Ct. 2645 , 41 L.Ed.2d 236 (1974), the court voided a patent because the inventor made several unqualified sales of the identical product. Id. at 1366-67 . Kock sold only one prototype of the invention to a production company.

In Cali v. Eastern Airlines Inc., 442 F.2d 65 (2d Cir. 1971), Cali submitted to his employer, Pan Am, an idea that became the kernel of a patented invention. In an infringement action brought by Cali against Eastern Airlines, the district court found that Cali, by submitting his suggestion to Pan Am, put the idea in public use. Since such submission occurred more than a year before Cali filed his patent application, the district court applied section 102(b) and invalidated the patent. In so doing, the district court “observed that Cali placed no restrictions on Pan Am’s use” of his idea. Id. at 69 . The Second Circuit reversed because “absence of any control by Cali, or any attempt to impose control, should not be elevated to the status of a per se test under the circumstances disclosed here and in the posture in which we receive this case.” Id. Thus, the Second Circuit held that the experimental process continued and that the public use bar was inapplicable, even though the invention was “out of the inventor’s hands.”

The majority also supports its holding by suggesting that the Supreme Court, in City of Elizabeth v. American Nicholson Pavement *663 Co., 97 U.S. 126 (1878), held that if there is to be an experimental purpose “tests made by one other than the inventor [must] be ‘under his direction.’ ” (cite omitted). Majority Opinion at 660. This is an inaccurate reading of City of Elizabeth . The Court there simply noted that when experiments are under the inventor’s direction, no public use occurs. Obviously, since courts have found experimental purpose even when the experiments were outside the inventor’s direction, the rule the majority espouses is questionable. See Cali, 442 F.2d at 70, n.3 (It may be unrealistic and inconsistent with the patent laws to require that the inventor maintain control over experiments for the transfer to qualify as a sale with an experimental purpose.); Cf. Dart, 489 F.2d at 1366 .

In fact, City of Elizabeth supports Kock’s claim. The case equates a public use or sale with “abandonment” of the invention. Id., 97 U.S. at 134 . Here, the evidence does not show that Kock abandoned the invention.

The majority also relies on a quote from Egbert v. Lippmann, 104 U.S. 333, 336 , 26 L.Ed. 755 (1881) that “if an inventor ‘gives or sells [his invention] to another to be used by the donee without limitation or restriction, or injunction of secrecy,’ there is public use (or public sale) within the statute.” Majority Opinion at 660. This rule does not void the patent here because Merry and Kock agreed to maintain secrecy; therefore, an injunction of secrecy apparently existed.