Toshiba and SanDisk have been in a number of joint ventures for some time now, but it looks like the two companies are now starting what could be a more drawn out break-up process, with SanDisk announcing today that it’s selling 30% of its manufacturing capacity outright to Toshiba in a $1 billion deal. For the time being at least, the two will remain 50/50 partners in the remaining 70% of the companies’ joint factories,