Karenarchey I mostly agree (surely though this is about picking on Zabludowicz?) but I don't know what a boycott on Zabludowicz means for people like me that don't have any contact with them anyway. So having gathered here, I'm now trying to process those thoughts. The causes of Palestinian oppression aren't localized to the Israeli state, and I don't think a boycott in support of Palestine should focus on Israeli institutions alone.
Turning back to what "Say No" means for me, I do know people involved with Zabludowicz, and obviously I can write to them and make sure they know where the money came from, and tell them that there are alternative support networks if they choose to "Say No" (I've spoken to one person already). It doesn't seem fair though to make this request of Zabludowicz people, when its not made of others. US/UK oil requirements (and foreign policy in general) are also to blame for the Palestinian situation. Some will say that Israel is more to blame, but they wouldn't be able to act with such impunity in the first place without US backing. Might it be desirable also to ask friends to turn down BP-sponsored Tate shows for Palestinian solidarity, or to boycott shows at American-run galleries? The public/private patronage situation doesn't mean someone can refuse Zabludowicz and then walk across the street to sell work, so boycotting Zabludowicz alone makes more (career changing) demands on some people than others (and not at all on me).
Where I've tried to point out the dirt in other funding sources on the "Say No" facebook page, in the Arts Council, for instance, or Deutsche Bank (as semi-spurious examples), I've found people saying "no, this is about Zabludowicz and Israel, we should focus on that", but my opinion is that the causes are wider and boycotting Zabludowicz as an isolated case (whilst being a good gathering point and for the right reasons), is not going to matter to very many people, and the people it does affect will have recourse to arguments about fairness, for starters (I'm just going to say use your imagination here). I'm also interested in practical questions, as Zabludowicz gives money to various other institutions, will these institutions be asked to cut ties? Will they be boycotted? Are we ready to increase our own funding contributions to make up the short-fall?
Volunteering time to institutions willing to clean-up their funding (dropping Zabludowicz money for instance), would of course displace a source of paid-employment for many young artists (and non-artists), but it could offer a preferable source of arts funding to private patronage and still be launched in support of Palestine. That reduction in art-gallery employment at multiple institutions is what refusing Zabludowicz money might really mean, and to me it seems a fairer and more effective way to spread the burden of refusal than if we stopped at asking the few people actively showing work at Zabludowicz's gallery to give up their show.