The Washington state Liquor Control Board (LCB), charged with launching the world's first regulated marijuana market for social use, expects to begin accepting applications for grower licenses April 17, with the first licenses to be issued in May 2013. State-licensed marijuana stores won't open until at least December, after marijuana-processor and retail licenses are issued. But several groups already have hired veteran lobbyists to influence the LCB, with business interests keenly aware of the potential.