bank sends new questionnaire after acquisition of my company is that necessary

New questionnaire after acquisition is normal, not exceptional

Yes, this is customary. During an acquisition, data that the bank is required to record changes: shareholders, control, sometimes the statutory name and registration number. The bank therefore cannot simply carry forward the old file to the new ownership structure. This applies in particular to identity questions — the legal name of the company and the registration number under which the enterprise is registered must be confirmed again after an acquisition, even if in fact nothing has changed.

What often does not need to be confirmed again is everything that relates to business operations themselves and not to the ownership structure: number of employees, turnover, sector, locations. If that data is unchanged, you can refer in your answer to the existing supply chain file instead of looking up each figure again. If you are unsure whether something has genuinely changed as a result of the acquisition, it is quicker to check than to guess: a change in shareholders affects identity and control, an acquisition without a legal merger often only affects the top layer of the file.

Where this follows from: the Trade Register Act 2007

The obligation to keep identity data current follows from the Trade Register Act 2007: an enterprise must have changes to the registered data made, and the bank must base its customer due diligence on the current state of that register. This is the reason why a bank almost always asks again for name, number and control after an acquisition, even if there is nothing else new in the questionnaire. Other parts of the file — such as the registered address or data on insurance — do not fall under this act and therefore do not automatically need to change unless the acquisition has in fact changed something about them.