H-1B with old employer - Multiple Filings Lottery

Recently I got a FT offer at E1 and joining is next week. They are filing my H1. But my old employer E2 didn’t want to lose me. So, he offered to file H1 on his end too. So, my question is would it be a problem, if my old employer E2 files my H1 as a future employee?
E1 and E2 are not related to each other

Well, if the companies are really not related, you can let them file it and you make the decision later…Usually with the new H1B Lottery System, there is chances of abuse, so multiple employers filing should be carefully considered based on the companies giving you the offer. Read below