word "included” used in paragraph three and the phrase “actually included” used in paragraph four? What was the manner of inclusion “presently represented” to Cowan? Does not the limiting phrase refer to the “agreements” designated in paragraph two? Some significance must be attributed to the use by Kline of the word “actually”, at least at this stage of the proceeding. Substantial ambiguities appear on the face of the letter of June 22, 1948. Another very substantial ambiguity, albeit a less apparent one, arises from the use of the phrase “advertising signs and displays” and the phrase “signs and displays” variously employed in paragraphs two, three and four. If, as the complaint alleges, Cowan made use of Gruen’s display by simply striking out therefrom the word “Gruen” and substituting in lieu thereof the word “Bulova”, did or did not Cowan use Gruen’s display in the final version of the picture? Under the circumstances, was there not an implied undertaking that if Cowan made use of Gruen’s sign it would do so only in order to advertise Gruen’s product?
There are many latent ambiguities as well. Did or did not the letter memorandum imply, an'obligation on the part of Cowan to use Gruen’s name on Gruen’s display, if the display was used at all? Was Cowan entitled under the provisions of the letter agreement or the contract made 'by Kline with Gruen to exact $25,000 from Gruen to be employed, according to Gruen, as a joint fund for advertising the picture and Gruen watches ? If Cowan was not' entitled to make this exaction, was Cowan, guilty of breach of contract? These questions also are ones which cannot be answered by an examination of the letter contract.
We are of the opinion that contemporaneous agreements not inconsistent with the terms of the letter may be introduced here, where reference is made to other agreements. Schmidt v. Cain, 95 Cal.App. 378, 380, 272 P. 803, 804. See also Henika v. Lange, 55 Cal.App. 336, 338, 203 P. 798, 800, in which it' is stated, “
where a portion only of the contract between the parties has been reduced to writing it is proper to* allow parol evidence as to the portion of the agreement not included in writing.
Johnson v. [D. H.] Bibb Lumber Co., 140 Cal. 95, 98, 73 P. 730 [731]; Williams v. Ashhurst [Oil, L. & D. Co.] 144 Cal. 619, 78 P. 28.” See also California Annotation, Restatement, Contracts. Extrinsic evidence also may be employed to resolve the ambiguities and uncertainties of the contract. Boddy-Steffner Co. v. Flotill Products, 63 Cal.App.2d 555, 561-562, 147 P.2d 84, 88; Detsch & Co. v. American Products Co., 9 Cir., 152 F.2d 473-474, and Simmons v. California Institute of Technology, 34 Cal.2d 264, 209 P.2d 581.
Gruen contends that by reason of Cowan’s conduct during the nine months’ period subsequent to the execution of the letter agreement Cowan became obligated to use Gruen’s name on Gruen’s display and that in any event Cowan is estopped by Cowan’s conduct and Gruen’s reliance thereon to deny that Cowan had elected to use Gruen’s sign and display. Expressly, we do not pass upon these allegations in order to determine whether or not they present causes of action available to Gruen pursuant to California law. Under our disposition of the instant appeal an opportunity will be afforded to the parties to present any evidence pertinent to the issues set up by the pleading, and any attempt to lay down applicable principles of law in the absence of findings of fact by the trial court would be to do little more in all probability than to render an advisory opinion.
As to the defendant Bulova the complaint specifically alleges that Bulova knowingly and maliciously interfered with Gruen’s contract rights. Paragraph XVI alleges that Bulova, conspiring with Cowan, altered the motion picture containing Gruen’s display by removing the word “Gruen” and substituting in lieu thereof the word “Bulova”; that these acts were committed in order to deprive Gruen of the “reasonably [to be] expected fruits of its agreements and understandings” with Cowan and to injure Gruen’s business, competitive position, dealer relations, reputation and good will. It is the law of