As a rule, no. The protective core of the standard contract — the text as announced by the Board, and the safeguards inside it — has to be preserved. Where you rely on the standard contract as your appropriate safeguard for a transfer abroad under the Personal Data Protection Law (No. 6698), it has to be used with the content the Board has determined, and the signed contract has to be notified to the Authority within five business days. That notification is not an afterthought; it is part of what makes the safeguard valid.
Departing from the protective provisions, or watering them down, puts the legal basis of the whole transfer in question and creates exposure to an administrative sanction. What you can do is deal with the commercial and operational terms that do not conflict with the standard text — price, service levels, additional technical measures — in a separate agreement or in annexes. The workable method is the same every time: leave the protective core exactly as it is, move the commercial negotiation into its own document, and make the notification on time.
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