The deals with Xstreet and OnRez have been finalised after months of talks, and will allow Second Life 'residents' to locate virtual goods for sale, and provide merchants with broader channels to sell their products.
The move forms part of several strategic initiatives underway within the virtual world, which Linden Lab hopes will increase the number of Second Life users in 2009.
"Linden Lab is expanding its footprint in the virtual world industry through four major initiatives: localising the Second Life experience in key markets around the world; simplifying the 'first hour experience' to broaden consumer adoption; enhancing the platform for enterprise users; and building our virtual goods marketplace," said Mark Kingdon, chief executive at Linden Lab.
"Content creators and merchants are pillars of the Second Life economy. With these e-commerce acquisitions, we will now be able to offer content creators and merchants an opportunity to substantially improve their businesses, while enhancing the Second Life experience for all residents."
Linden Lab will consolidate the two marketplaces on the Xstreet SL platform, to offer a single online shopping experience for customers and merchants.
Although Xstreet SL merchants and customers will be largely unaffected, merchants using OnRez will need to migrate their accounts and product listings over to Xstreet SL and customers will need to transfer their balance to a Second Life account by 11 February.
Linden Lab said that the global market for virtual goods is worth an estimated $1.5bn (£1.08bn) a year, and that Second Life residents bought and sold more than $360m (£260m) worth of virtual goods and services in 2008.
The acquisitions are expected to help grow the Second Life economy even more by offering a centralised platform for buyers and sellers to transact virtual goods and services online.
Much like traditional online shopping sites, Xstreet SL provides an online catalogue, where Second Life residents can browse, purchase and sell related virtual goods and services.
Second Life has its own currency, Linden dollars, which can be bought by residents with real money using a PayPal account. Linden dollars even have a quoted exchange rate against the US dollar.
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