Legal Question in Real Estate Law in California

There is no bright line rule on that. If they recently died of some highly communicable disease, you better disclose. If grandmother quietly passed in her sleep unexepectedly ten years ago, you probably don't need to disclose that. The test is whether the information would materially affect the value or desireability of the property. There is a statute that puts a five year limit on the duty to disclose certain deaths, but I'm not sure if it is all deaths or not without looking it up, which is beyond the scope of a free answer.

Rule of thumb ... if the question begins with the words "Do I have to disclose ...", the answer is almost always "YES!" Why? Because you are required to disclose anything that might affect the value or desirability of the property. All you will need is for someone to come back to you in 2 years saying that you failed to disclose this fact, and that they are fearful of being in a house where someone died in it. If you thought about it, don't you think a buyer would consider it?

Yes, read the official forms you have to sign.