Xenos Group, Inc.
- Provides data and electronic document transformation solutions.
- http://www.xenos.com/

TEXTML
- native XML database server for content search and retrieval, supports WAP
- http://www.ixiasoft.com/

OpenLink Virtuoso
- A cross-platform, Internet data integration server, implementing native XML storage, web, file, and database server functionality and universal data access middleware as a single server solution.
- http://www.openlinksw.com/virtuoso/

X-Hive/DB
- XML Database in form of a Java-based persistent DOM implementation.
- http://www.xhive.com/

Infonyte
- XML database built on a PDOM and a XQL engine.
- http://www.infonyte.com/

Xyleme
- Dynamic data warehouse that is an indexed XML repository capable of answering queries from applications and users.
- http://www.xyleme.com/