Did Polaroid's patents on integral photography describe a different technology than what Polaroid used?

I had a colleague at Polaroid in the 1980s who told me that the patents Kodak was accused of violating did not describe the system that Polaroid was actually using in its SX-70 and Spectra film, but instead described a chemistry that Polaroid had decided not to use. Polaroid kept the better system as a trade secret.

I’ve looked through coverage of the Polaroid v. Kodak case for several years and have been unable to find any substantiation to this claim. I’ve also read in some cases the same plants were producing both Polaroid and Kodak film. So I’m not sure what’s really going on.

My colleague also told me that during discovery a memo from Kodak was found which stated that Kodak knew that it was in violation of the Polaroid patents, but that Polaroid would probably never sue because of the expense. Likewise, I’ve been unable to find reporting of this memo. You would think that it would be in the court record, but I haven’t been able to find it (and I assume it’s huge).

So I’m looking for an answer to this question — Did Polaroid’s patents on integral photography describe a different technology than what Polaroid used? I don’t know how to even research this question, other than lots of Google searches…