Yes, other than the stock market activity, there is nothing about this company till now that suggests any kind of foul play.
The problem is that financial irregularities are not easy to detect in case of financial firms.
If a non-financial firm manipulates its numbers, the cash flow statement usually (but not always) reveals the stresses in the business.
(There can be cases like DCHL, where the company was under-reporting debt and thus was manipulating the cash flow statements too. However these are exceptions)
Cash flow statement is not very reliable in case of financial firms and therefore investors have no choice but to believe financial statements published by the management, assuming that the auditors are doing their job sincerely.
Yes Bank's stock price erosion has little to do with what is happening in the boardroom.
It has more to do with the tightness in the money market and overall economic conditions.
Kotak's Sanjeev Prasad today expressed doubts about Yes Bank's loan book in an interview on CNBC TV18. It is surprising that in spite of deteriorating economic conditions and high exposure to SME sector, Yes Bank has hardly seen any increase in NPLs in the last few quarters. I will post the link to the interview as soon as it is published on moneycontrol.com.
One of the concerns that market has on Yes Bank is just the book itself. It is one of the few banks that has not seen any NPL problem in the last 1-2 years and in a cycle it is completely unscathed as far as NPL problem is concerned.
Given the fact that Yes Bank has most of its loan book to the corporate and Small and Medium Enterprise (SME) segment, something like 86 percent of the loan book is to the corporate and SME segment. In that context, if a bank has pretty low NPLs then unless you get some conviction on that, the bank may continue to languish at current valuations.