They had several steps in the interview process. Step 1: HR Screen - Simple. Went over the resume and asked why I was interested in the position. Had me write an email with answers to 5 different questions, along the lines of Most challenging thing that I ve done in the recent times, what I'm most proud of.. etc. Step 2: Phone call with HR - more of the previous step. Step 3: Technical Phone Screen with Project Manager. - Again discussed resume, and past experience and what I look forward to doing at Align Technology. Also, a couple of technical questions were asked. They were pretty simple. Step 4: Skype interview with the Senior Research Members. They went over my experience and what I am looking forward to doing at Align Technology. Then, they asked several technical questions regarding aligners and how they work. Forces and moments required to move the teeth in a specific direction, free body diagrams etc. It was not easy for someone who has not worked with aligners in the past. Overall interview experience was ok. This was the last step in the process for me. I was told that Step 5 would be direct interview at the company. However, I got a rejection email from the HR 5 days after my Skype interview.

Two stage Interview Process: 1. First technical interview about experience and skills: was confronted with an actual business problem they are facing and was asked about how I would go about solving 2. Coding and Machine Learning Interview: was held as two separate sessions - the coding one was a classical Leet Code interview with additional technical questions on ML concepts in the final part of the interview - for the ML Interview I was asked to select and review a paper (I chose "Attention Is All You Need") from a list they gave me which we then discussed in quite a lot of detail