India's market regulator is said to be considering more stringent rules for participatory notes as part of efforts to check the flow of black money into stock markets. Previous moves to intensify scrutiny of the instruments, which afford a greater degree of anonymity than other avenues of investment, have alarmed investors into pulling their money out or threatening to do so. The Securities and Exchange Board of India (Sebi) is now looking to make it mandatory to collect `know your client' (KYC) details of participatory note (P-Note) holders and is likely to take a decision to this effect at its board meeting scheduled for May 20, said people familiar with the matter. Experts said the move is likely to help hasten the eventual phasing out of participatory notes altogether. The regulator has also proposed that offshore derivative instruments (ODIs) be transferred only to subscriber entities eligible to invest in them as per Indian regulations. Sebi didn't respond to quer...