I think the indication you have gotten is correct. Malpractice insurance is offered on a claims made basis - not an occurrence basis. The primary difference is simple - for occurrence based insurance, the coverage must be in place when the occurrence that gives rise to the claim occurs (hence the term "occurrence based". For claims made insurance, the policy must be in effect when the claim is actually made - which will be definition be some time later.
If an Architect drops coverage between the time the occurrence arises and the claim is made, there is no coverage in effect when the claim is made, which is probably the concern the Owner is seeking to address. However, while one can understand why an Owner would ask that question, the reality is that occurrence based malpractice insurance is simply not available.
For a time, many carriers offered project policies, but the problem with that was many Owners - and even Architects (since the claims did not apply to their general malpractice policies) considered those policies little more than slush funds to cover additional project expenses. Carriers lost a fortune on those policies and they generally stopped offering them, although some may do it on a limited basis again (understand that it is very expensive).
This sort of question engenders another one. The Institute should engage with the professional liability insurance industry so that the profession and the membership is better educated on these sorts of things and even has a voice in the development of insurance products that would benefit the average practitioner. However, the Institute has passed on the opportunities that have presented to do that, and in my opinion that isn't a positive thing, but be that as it may.
As a consequence, besides your broker, there is really no other source of information on questions like this. The best advice is find a good one you can trust, and take their advice. On this question I think the advice rendered is correct. Malpractice insurance (and not just for Architects) is offered on a claims made basis. One possible compromise would be for you to place a indication in your policy to the effect that if the coverage is set to expire, notice will be afforded to client who has expressed concern. That should be doable, but in general the market simply doesn't offer occurrence malpractice policies to any professional.
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Frederick Butters FAIA, Esq.
Frederick F. Butters, PLLC
Southfield MI
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