I have verifiable information regarding the founder of a technology company who has engaged in highly unethical, potentially fraudulent business practices and has been able to operate under the radar for several years. The company he founded is backed by a private equity firm. He was asked to step down several years ago and officially went into "retirement". After a year, he pursuaded the powers that be to green light his return as director of sales, essentially returning as a 1099 sales person. Prior to negotiating a return, he started a competing consulting business for the purpose of syphoning/diverting clients away from the company he founded. The CEO, CFO and other Principals had no idea and still don't. I believe this is largely due to a certain trust factor with him being the founder as well as very loose controls. I'm not sure what his ownership percentage with the company is, if any, however, I feel morally obligated to let the appropriate people know about his nefarious activities. I want to remain anonymous as the individual I'm writing about is in my opinion, a very dangerous man who has gotten away with a lot of unethical and illegal activity in his life. What is the best way to go about this and to protect myself in the process?