Some history:
In the US, this is very tightly controlled and regulated. Although stock market securities insider trading is a relatively new crime around the world (20-30 year old), the United States is exceptional for offering the longest sentences for it, although it is still far more lucrative than and carries lower sentences than something like petty larceny. The perception of illegal insider trading has changed in the US over the years, although it is based on much older fraud statutes the regulators and the courts have only really developed modern case law against insider trading in the past 20-30 years.
The US relies on its vast network of registered broker-dealers to detect and report abnormal trading activity and the regulator (SEC) can quickly obtain emergency court orders from rent-a-judges (Administrative Law Judges) to freeze trader's assets to prevent them from withdrawing, or quickly enacting sanctions. So this reality helps deter trading on material inside information.
So for someone that needs to get an information advantage on the market, it is [simply] necessary for them to rationalize how this information could be inferred from public sources.
Similarly there is a thin line between non-public information and public information, the "lab experiment" example would be material insider information, but the fact that there will be litigation over a company's key patents may be "public" as soon as the lawyer submits the complaint to the court system.
It is also worth noting that there are A LOT of financial products trading in the capital markets, and illegal insider trading laws only applies to trading of shares of a company. So if a major holder in gold is about to liquidate all their holdings, being short gold futures is not subject to civil and criminal sanctions.
Hope this helps. The above examples should help you understand what kind of information is material inside information and what kind is not, and how it is relevant to trading decisions.
