Legal Question in Business Law in California

it is fraught with dangers, and you wil likely be sued. They are difficult and expensive cases for an attorney to bring and to defend.

Under certain circumstances and if done properly, you can. As Mr. Marman notes, however, it is easy to break the laws protecting trade secrets and proprietary information when you do that, and even if you don't break the law, the likelihood of getting sued and having to prove you did not break the law, at great expense, is very high.

Sure, at the risk of violating the unfair competition rules and getting sued. Do it right to avoid that.

To be somewhat more specific, there are two main areas of caution: misappropriation of trade secrets, and interference with contract.

As to the former, trade secrets include any information that your previous employer compiled or collected, including but not limited to, customer lists and data about customer and prospective customer needs, preferences, buying habits, etc. that is (a) not widely known or available from directories, on line, trade publications, etc., and (b) which the previous employer treated as private, privileged or secret by taking some kind of steps to avoid its widespread disclosure.

Interference with contract, or its close kin, interference with prospective economic advantage, are business torts that generally consist of trying to induce someone to breach a contract they've already made, or more generally, maliciously interfering with someone running their business.

California law encourages business competition, but not with the other guy's secret info, nor by causing the other guy's customers to breach their contracts.