The Sourcery interview questions

The Sourcery contacted me and asked me to interview with a tech startup that they said they were working with. They explained it was a remote-work opportunity so the entire interview process would happen over the phone. I accepted. During the phone interviews I confirmed to both The Sourcery and the startup –in four opportunities– that I was available to work full time (this is a relevant point). After passing these phone filters I was then asked to take a "coding challenge". To my surprise, they asked me to write a software algorithm that is commercially useful in the startup's field, i.e . it can definitely be used in their technology. I still wrote and sent them the code, assuming they were acting in good faith. This project took many hours of work. But after I sent them the code, The Sourcery and the startup disappeared. They ignored my emails requesting a status update. Finally after three weeks, The Sourcery sent me a non-apologetic two-line email saying that, although the startup believed I was an "incredibly strong candidate", they thought I would not be available to work full-time (despite my numerous confirmations during the interviews). More precisely, The Sourcery falsely stated that I owned a "startup" and that this (inexistent) company would keep me too busy. This seemed really fishy to me, since I do not own any startup, and I had clarified to them multiple times that I was actively interviewing for full-time jobs. Why did they ask me to spend hours writing code (commercially-useful code) for them, if they believed I was not available to take the position? I requested further clarification but neither The Sourcery or the startup ever replied. Then I started investigating the startup that The Sourcery said they were working with: I found no traces of it being an actual, registered company. It's not on Glassdoor either. When I asked the startup's staff whether they were a real company, they did not reply. The Sourcery never cared to clarify this either. Even more eye-raising, the startup founder (and sole investor) that The Sourcery presented to me seems to have eye-raising reviews on Glassdoor regarding one of his previous companies: "Owner is delusional and has no grasp on reality.", "Don't just look the other way, RUN.", "Accept Employment at your own risk", "Run in the opposite direction", etc. You can find this easily just searching for those phrases at Glassdoor.com To complete this strange picture, after I was turned down the startup staff asked me to forward my emails with The Sourcery. So apparently these two companies were not in communication while interviewing me? Summarizing: The Sourcery asked me to interview for a startup that doesn't appear to be a registered company (as of over a month after the interview). The Sourcery was co-participant in an interviewing process where I was asked to develop commercially-useful code for free, despite the fact that they believed I had a "startup" and would not be available to take the job. After I sent the code The Sourcery disappeared for an entire three weeks and did not promptly reply to my email requesting status. They didn't reply either to my request for clarification for their surprising statement that I owned a "startup". The startup's sole investor and founder seems to have unusual red-flag reviews from employees of his previous company on Glassdoor. Internet records suggest he might be heavily involved in patent litigation against huge companies. All this data is easy to find by just googling with the information I provided. I wish I had done this investigation before interviewing.

Had a basic call with the internal recruiter, had a recruiting exercise to be completed within a certain time frame and then had a last call with a lead recruiter. Overall very seamless/smooth process.