Open source accounting and ERP product maker Open Systems Inc. has expanded to the Pacific Northwest with the purchase of longtime reseller MicroAccounting Systems Inc.

The staff at the Beaverton, Ore.-based firm -- including president Joe Taylor -- will remain and continue on as the Pacific Northwest office of Open Systems. This is the third such acquisition in as many years for Open Systems, which bought its Greenville, S.C., and Edmond, Okla.-based reseller InterMicro in 2012 and Orange County, Calif.-based partner Independent Computer Services in 2011.

MicroAccounting Systems (MASI) has served midsized businesses in Oregon and Washington since 1983, specializing in retail, manufacturing, wholesale distribution, and other inventory-intensive industries.

“MASI has been successfully serving clients for 30 years, and we’re pleased to bring their expertise into the Open Systems family,” said Open Systems chief executive Michael Bertini. “Joe Taylor and his team will continue to serve those clients, as well as represent Open Systems software in the Pacific Northwest market.”