What we do

How does an artificial intelligence learn to listen and speak? The same as a child does. You need to teach it the right words and concepts to understand the world around it. At Sigma, we collect, prepare and label the data that companies use to train AI programs to understand speech, text, images, videos and more.

Our annotators are at the heart of this process. With their diverse backgrounds, experience, language skills and perspectives, they interpret and label AI training data with a human touch, helping AI serve humanity better and with less bias.

Who we are


Humans are at the heart of everything we do. From our inclusive annotator teams to the way we design processes to the customers we choose to serve, we do so with the purpose of making human lives better.

Challenge lovers

We’re at our best when we tackle complex challenges. Instead of sticking to standard solutions, we strive to find the best approach to solve a problem — and we’re keen to grow and learn new things to get there.

Empathetic collaborators

Discussion culture and empathy go hand in hand at Sigma. When we put our egos aside and put ourselves in our teammates’ shoes, it allows us to talk through even the toughest situations together.

Expert advisors

From our founder’s decades-long experience in AI research to our annotators with deep knowledge of over 250 languages and dialects, everyone at Sigma is an expert in their area and has something important to contribute.

What we offer

Flexible vacation

Take time off whenever you need it, in consultation with your manager


Full health coverage for you and your family with the Spanish Health System

Risk prevention

We care about your safety at work, so we design workstations and common areas to minimize risks.

Parental leave

All new parents, whether birthing or not birthing, are eligible for paid leave

Family accommodations

Adapt your work schedule or work from home according to your family needs

Drinks at our cafeteria

We offer a variety of coffee, milk, tea, and herbal infusions in our cafeteria

Continuous training

We schedule a variety of annual workshops and seminars for all employees


We accompany you in navigating the next steps of your professional career

What to expect when you apply

Recruiter profile

Adama Toure Sarr

Project Manager & HR, Madrid

Hello, I’m Adama! I’m originally from Senegal but grew up in Zaragoza, Spain. I’m in charge of the recruitment process of the transcribers who will be working in our secure facilities. I take care of your application every step of the way, from first contact to hiring. If you’re looking for a multicultural environment and language exchange at work, send us your CV!


Annotators and linguists across 5 continents


Nacionalidades representadas en los cinco continentes


Languages and dialects spoken


Of annotators are women, 94% of project managers

Open Positions

Please apply online via LinkedIn or Indeed. Sigma will only consider applications that are submitted online. Applications that are sent to Sigma via the “Contact Us” form will not be considered for placement.