I am currently working at company A. I got a job offer from company B after 10+ hours of interviews, references, a thorough background check, many conversations with HR etc. I am planning to give my boss at company A my two-weeks notice, take a couple weeks off and then start at company B.
Company B has sent me an offer letter, employment agreement (with comp detailed), benefits package etc. Additionally, they have given me confirmation over the phone and email (when I asked) that we both accepted this offer/agreement. Company B is 1000+ employees, well-known and has an excellent reputation in the industry. However, I'm told it's company policy that the agreement isn't actually signed by either party until my first day.
I've never experienced something like this before. Is this a red flag? Should I be pushing back? Does a signature offer any additional protection at all? What possible reasons could they have for this policy?
If it helps, I live in the USA and this is a US based company I would be working for.
Any help is appreciated, thanks!
Edit: As asked in the comments below, all of the above conversation was had via email and phone call with my contact at HR. However, HR and all the other members of the team, future boss, boss' boss etc. have made it very clear they are excited for me to join. I've spent hours chatting specifics with some of these people. I received 15+ pages detailing all the exact contract specifics and this is the one we will sign. Everything but the signature issue is seemly great! However, I just don't see any legitimate reason why they want to wait...