Hi @Laford, Thomas,
Per my research, we are unable to set file is checked in with Copy.CopyIntoItems. You could refer to the parameters in the function. There is no such parameter relate to checked in.
I feel regretful to inform you that it turns out to be a by-design one. It is highly recommended that you can vote this ticket. Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future. Thanks for your understanding.
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