Contracting at Large Tech Companies

I'm looking to start my career in tech and been in the job search for over a year now. At this point I'm looking to take whatever opportunity I can. I'm happy that many contracting agencies have contacted me about opportunities and submitted me for roles, but I never hear back from them. Based on the number of emails I've gotten this week, I'm thinking maybe it's better that I contact one of the recruiters of the company directly and ask if they have any temporary roles.

Are any of the big tech companies allowed to hire contractors or temp roles without an external agency?

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