That's always tricky.
I assume (please correct me if I am wrong) that you worked with other people on this project. Commonly, there is at least a PI (primary investigator --- i.e., project lead) and there might have been some Master/PhD students/Post-Docs helping with the workload.
If it was collaborative work, you need to at least inform them.
Most likely: you need to add them as co-authors (anyone who contributed).
You should be aware that many things can be a contribution: library access, equipment access (i.e., your working machine), ideas, feedback, data, funding, and the work of people.
Depending on how important the contribution is, the contributor needs to be an author or can be mentioned in the acknowledgments.
Note, that this goes both ways. If they write a paper about the stuff that you did, they need to acknowledge you too.
So, the chances are significant that you need to acknowledge them somehow.
Safest would be to let them know and add the PI as a co-author.
Note: This is how it is handled commonly in academia and maybe an ethical point of view. Legally, I would recommend looking for legal advice regarding intellectual property.