IBM has a 53 per cent market share in the market for SOA engines, according to a study by Wintergreen Research. 

Big Blue is the only vendor achieving a double-digit market share. Microsoft ranked second with seven per cent, while BEA, Tibco and Sun Microsystems' SeeBeyond logged in at two to three per cent. 

Susan Eustis, president of Wintergreen Research, attributed IBM's lead to its middleware portfolio and the fact that all its products have an SOA engine built in natively.

Many competing products use adapters that slap on SOA functionality to existing middleware, Eustis told vnunet.com.

IBM boasted at the Impact 2007 conference that it has recorded 4,500 SOA 'engagements', where one customer can count for multiple engagements. This indicates that fewer than 9,000 companies are currently using SOAs worldwide.

Wintergreen Research defines an SOA engine as middleware that provides a repository or process implementation for reusable code.

These engines include an application server, repository, enterprise service bus, XML compression, security and messaging platform.

Companies worldwide last year spent about $1bn on SOA engines. The research firm projects that this will grow to $3.7bn by 2013, amounting to 20 per cent annual growth.

Overall adoption of SOAs will far outgrow sales, however, as Wintergreen Research predicts prices of SOA components to fall from a current peak of $7,200 to $100.

But SOA middleware will not be the big growth opportunity for SOA vendors. Eustis predicted that selling online services will provide a $17bn market by 2013, as companies find out that externally developed code offers better performance and reliability than internal creations.