Le blog du droit européen des brevets (in French): a must-read to keep up-to-date with the case law of the Boards of Appeal of the EPO, since 2007. The Friday posts on the “invention of the week” are also a good introduction to weekend relaxation.
The IPKat (in English): an unsurpassable source of information on all IP-related news, mainly (but not exclusively) UK-oriented, by a team of authors from different backgrounds. If anything majors happens in the IP world, you can be sure that the news will instantly break on the IPKat.
Tufty the cat (in English): yet another feline blog commenting on UK and European patent law developments.
EPLAW patent blog (in English): reports on decisions from various European jurisdictions by a multinational team of patent specialists.
Just Patent Law Blog (in English): one post a day on EPO case law. The headline says there are no trademarks, no Mayo and no cats. Ouch.
The SPC blog (in English): for all SPC nerds, as the name indicates.
PatLit (in English): this weblog focuses on patent litigation, mostly in Europe and the U.S.
Patently-O (in English): taglined as America’s leading patent law source – no less.
Brevet, Recherche, Invention, Savoir-faire, Base de données, CCP, leur contrefaçon et les actes associés de concurrence déloyale (in French): this blog by attorney at law Philippe Schmitt sometimes helpfully reports on very recent case law decisions.
Delta patents (in English): dedicated to the case law of the Boards of appeal.
Jurisprudence des brevets en France (in French): a thorough report on French patent decisions, by an anonymous and quite mysterious author. Unfortunately, the blog seems to be currently off.
K’s law (in English): an extremely prolific blog on decisions of the Boards of appeal of the EPO. Unfortunately for its readers, it was shut down in 2014 when the blogmaster got promoted from commenting on decisions to actually drafting them. But the archives are still online.