In general, you are going to have a difficult time making a given piece of info part of the record on appeal if it is not clear that the trial court considered that info in the first place. Here, if there is any indication from another source that the trial court actually viewed the info under the sticky (for example, if the court made a comment in a hearing or a minute order that referred to that info, or if respondent would stipulate to what was under the sticky), you could probably augment the record on appeal with the "un-stickyfied" version of the document. (See Cal Rules of Court 8.155.) You could also try to augment the record even if there's no evidence that the trial court saw what was under the sticky, but that strikes me as a tough sell. More fundamentally, though, I'm wondering if the "sticky" controversy actually matters to the substance of the issue being appealed. If what was under the sticky was just some random detail, then the fact that it was obscured by a post-it, while aggravating and perhaps dishonest, really doesn't make any difference at this point. It's worth spending energy on it in the appellate context only if the info under the post-it somehow casts the issue that you're appealing in a different light.
What makes you think the trial court did not lift the sticky note to examine the document? Why was the sticky there? Did you object to it on relevance or alteration grounds? if not, why not? I am not admitted in Cal., but I don't think the original papers are going to be before the appellate court (unless it's an original-record appeal from a lower court).
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