The groups, which represent the interests of developers, vendors and consumers, will merge in order to increase their reach and market penetration.
The OW2 Consortium works with middleware, applications and projects, including ASM, Bonita, eXo Platorm, Funambol, JOnAS, Joram, Orbeon Forms, PEtALS, SpagoBI and XWik.
The OSA, meanwhile, was created to encourage open-source adoption in enterprises, making the merger almost inevitable, according to the leaders of both groups.
"When you look at each organisations' strengths in technology and market presence, as well as the global positioning of our members, OSA and OW2 look like two puzzle pieces waiting to be put together," said OW2 chief executive Cedric Thomas.
"We can do much more together than apart, and a combined entity will provide a single voice for open source worldwide and a unique global pool of open-source resources."
The groups said in a statement that they will support the development of a diversified code base and portfolio of open-source components, and promote their use in enterprises, academia and government.
"Open-source solutions meet business-critical needs while offering flexibility and cost advantages to end users," said OSA president Anthony Gold.
"By merging OW2 and OSA, we can drive that message home to IT professionals, chief information officers and chief executives throughout the business community, education and government."
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