(Reuters) - OTC Markets, the operator of three U.S. over-the-counter equity markets, is rolling out tighter reporting standards and eligibility requirements for its venture-stage market to crack down on stock scams and bolster transparency, the company said on Wednesday.  On May 1 for its OTCQB market, OTC Markets will introduce a new minimum one-cent bid price requirement and will require the company's chief executive or chief financial officer to certify that its reporting obligations are current and that disclosures about shareholdings, officers and corporate profile are correct. The bid requirement, in which stocks must have been quoted for at least 1 cent daily over a 30-day period or be dropped from the market, aims to ferret out companies that fall prey to dilutive stock fraud schemes and promotions, OTC Markets said. OTC Markets also will charge a one-time $2,500 fee for new applicants and an annual $10,000 fee for companies trading on its markets. Foreign companies that are listed on a qualified stock exchange and are current in their U.S. reporting obligations will be allowed to trade on OTCQB, OTC Markets' middle-tier marketplace. In the past, they traded on the lowest "pink" tier. On Tuesday, the two most actively traded stocks on OTC Markets on Tuesday were French dairy products maker Danone SA and Swiss pharmaceuticals Roche Holding AG . Trading volume on OTC Markets was 20.1 billion shares on Tuesday, about three times that of all U.S. stock exchanges and other trading venues. But the value traded, $1.4 billion, paled in comparison with the $263.4 billion executed on the other exchanges and venues, data from BATS Global Markets showed. (Reporting by Herbert Lash )