Investments into the domestic capital markets through participatory notes, or P-Notes, dropped to 2.12 lakh crore rupees in September. But investments through this route had hit a five months high of 2.16 lakh crore rupees at the end of August.P-Notes are typically instruments issued by registered foreign portfolio investors to overseas investors who wish to invest in Indian markets without registering themselves directly in India to save on time. But they still need to go through a proper due diligence process.