Sorry for the late reply.
Must be due to IRGC support for Russian operation in Ukraine.
@SalarHaqq @Hack-Hook
It's basically a bunch of long-time enemies of the Iranian people, namely EU regimes, doing what enemies are expected to do: translate their hostility into deeds.
They're enraged at Iran's burgeoning ties with Russia of course, and also at the Raisi administration's steadfastness on the nuclear file as well as its principled refusal to reactivate the JCPOA unless necessary guarantees are offered by the west; Iran's increasing stock of enriched uranium, new measures to protect nuclear installations from sabotage and potential air strikes, such as the immense underground facility being constructed at Natanz. We could add the way in which the current Iranian government has boosted the long dormant national space program and the progress it implies in terms of ICBM technology. Or Iran's relations with her network of allies in the region and beyond, rock solid as ever.
But of course, timing-wise these hollow EU antics come on the heel of recent western- and zionist-backed riots, which have fizzled out and utterly failed to compromise political stability in Iran. However the enemy needs to capitalize on the gigantic propaganda and psy-ops campaign they invested in. Hence the EU parliament's vote and possible subsequent addition of the IRGC to their terrorism list.
Hollow because contrary to the bogus narrative peddled by the enemy's media mouthpieces (BBC, Saudi International etc) such a move onto itself will not affect the Iranian economy in any meaningful way. Anti-Iran propaganda outlets claim some companies "linked to" Sepah have kept trading with European ones and will no longer be able to do so, but fact of the matter is that since the USA regime is applying its own unilateral sanctions in an extra-territorial manner, meaning that the regime in Washington will sanction any European company that chooses to ignore USA sanctions on Iran, and given that Sepah has been on America's terrorism list since Trump, it means no European company would have traded with "IRGC-linked" entities anyway.
At most will they arbitrarily sanction a few Iranian companies and claim ex-post that they're related to Sepah, only to fool people in believing their latest decision is having an impact on Iran. Simultaneously, this will provide Iran with every justification she needed to take additional measures against the EU.