The petition "Für den Erhalt des privaten Sammelns" reached 9000 signatures today, with the German and foreign contributions almost equal. With 33 days to go to the end, there are 9309 supporters, 4769 in Germany. The initial impetus is flagging now.
I came across a link to the petition on a stamp-collectors' webpage, which raises the question who actually is signing. It is easy to assume these are all antiquity collectors, but The-Sky-is-Falling Ursula Kampmann assures other collectors that they will be affected: Betroffen sind alle, die sich auf traditionelle Sammelgebiete wie zum Beispiel Bücher, Briefmarken, Möbel, Keramik, Münzen, Oldtimer oder Bilder spezialisiert haben. Well, that is not actually true, because in some of these categories, it reportedly will only affect certain classes of material - so for example in the case of paintings only of a certain age and price range. But it seems by these means various groups of collectors are being tricked into signing the petition. Not ll of the signatures though are those of dugup antiquities collectors.
Also the draft which Ms Kampmann reported seeing was one that contained the proposal that "the supreme state authority and authorized experts [will] have access to flats and buildings where the cultural goods are held" (which mirrors current law in at least one neighbouring country). This however was one of the measures removed from the draft a few days after Ms Kampmann wrote about it (Statement zur Pressekonferenz Novellierung des Kulturgutschutzrechts Jul 15th 2015), but it seems to be one of the things the petition she wrote protests about. If so, the petition in effect concerns an out-of-date draft of the proposed law. So once again, collectors are not properly informed what it is they are signing and why.