Elon Musk has said & written, recently that other vehicle manufacturers are progressing too slowly with electric vehicles &, as a result he is contemplating making Tesla's technology available to them. This will be, "... in the spirit of the open source movement, for the advancement of electric vehicle technology." He has also come to doubt the merits of patents, describing a patent as, "... a lottery ticket to a lawsuit".
Firstly, at the recent 2014 Tesla Shareholders' Meeting
http://chargedevs.com/newswire/does-tesla-plan-to-share-its-battery-technology-with-other-automakers/
Secondly, in a post entitled, "All Our Patent Are Belong To You", in the Tesla Blog, 12 June 2014, US Pacific Time
http://www.greencarreports.com/news/1092697_musk-tesla-going-open-source-lifting-patents-in-good-faith
Tesla Shareholders' Meeting 2014
Part 1
http://youtu.be/FQMOq-qWVBg
Part 2
http://youtu.be/FQMOq-qWVBg
Tesla Blog post, "All Our Patent Are Belong To You", 12 June 2014 US Pacific Time
http://www.teslamotors.com/blog/all-our-patent-are-belong-you / wall of Tesla patents lobby Palo Alto headquarters removed Tesla Motors accelerate the advent of sustainable transport EV electric vehicles lay intellectual property landmines behind us inhibit others first company patents they serve merely to stifle progress entrench the positions of giant corporations enrich those in the legal profession rather than the actual inventors create patents copy our technology massive manufacturing sales marketing power overwhelm Tesla major manufacturers small non-existent large automakers producing electric cars limited range limited volume zero emission cars Tesla to build electric cars carbon crisis market is enormous small trickle non-Tesla electric cars produced enormous flood gasoline cars LiIon lithium ion battery charge recharge charger SuperCharger /