db4objects, Inc. software

db4o for Java 5.5     
db4o (database for objects) is the open source object database, native to Java.

db4o for Mono 5.5     
db4o (database for objects) is the open source object database for Mono.

db4o 5.5     
db4o (database for objects) is the open source object database (Java and .NET)

db4o for .NET 5.5     
db4o (database for objects) is the open source object database, native to .NET.