TeamPatent offers web-based knowledge authoring and collaboration tools that help attorneys focus on strategy rather than the mechanics of patenting. We are a fully-funded, early-stage startup, founded and run by an HP Labs senior researcher with extensive patenting experience. Initially, we're building a browser-based, collaborative editor with novel tools to express complex relationships within and between documents (the homepage screenshot illustrates one of these tools--associating textual terms and drawing callouts).

This is a late introduction of dojox.sketch, which was contributed to dojo foundation by TeamPatent.

dojox.sketch allows users to place/manipulate shapes on top of a background image, zoom/pan, and (unlike other open-source Javascript drawing tools) supports undo/redo. It's designed for collaboration, encoding changes as diffs to the SVG document (the diffs can be transmitted to collaborators). It's cross-browser, transposing SVG to VML and vice versa on the frontend.