I am not a lawyer, I'm definitely not your lawyer. Never act on material non-public information (see https://money.stackexchange.com/a/55407/22837 for a good description of what I mean by that).
If you were to provide this rumour (which is effectively all it is - you have no evidence of its veracity but let's assume it's true) to a news outlet of record (as defined in your jurisdiction) and they were to publish it you could safely trade on that information after publication. That is the only totally safe way to trade without being flagged for insider trading.
If information can be shown to be "in the public domain" then this is not strictly necessary. This means that if you published the information yourself on a website (for example) where the information is taken to be more than an opinion or a rumour and where it could be reasonable assumed that a reasonable investor would find the information if they searched for it then you have an argument that the information was public.
As an aside and definitely not advice sharing it with your friends in your local pub would not be sufficient, sharing it with mine in the pub by my office might be. I'm close enough to an exchange that if I went to the right pub at the right time and was sufficiently persuasive it could be argued that a large proportion of market participants had heard the information and had reason to believe it were true. If you shout it loud enough that everyone can hear then it is "common knowledge" - this has a legal definition here (the UK) and in many jurisdictions that is unimportant here.
The key is that in order for material information to become public it must be freely available to any market participant who is looking for the information. It does not matter who publicizes it.
I'll try to enhance this with some references later as this information is coming from experience and the CFA level I guides which are copyrighted information.