SAN FRANCISCO — IPO activity in the first half of 2015 is down markedly from last year, both in quantity and capital raised. The slowdown is particularly apparent in California, leaving Valley deal lawyers more focused on secondary offerings, private financings and mergers.

Several lawyers said they expected a busier start to 2015 but are optimistic that the current stall is the calm before a boom.

According to a recent report by MergerMarket, the volume and dollar value of initial public offerings is roughly half of what it was in the first six months of 2014. Of the 10 largest IPOs for U.S.-based companies this year, none involved a California company.