More companies are benefiting from a lucrative tax subsidy that permits large, profitable corporations to get checks from the state without paying any Iowa income tax. The latest annual report from the Department of Revenue on the use of the Research Activities Credit (RAC) shows that 248 companies claimed $50.1 million from the program in 2015. The number of companies claiming the credit in each of the last two years is 55 percent higher than in 2010, the first year of full-year annual reports on use of the credit. Most of the credit claims — $42.1 million, or 84 percent — were paid out as checks, not as tax reductions, and 88 percent of the claims were by very large, profitable companies.