On September 25, Atomera announced our first commercial license agreement with Asahi Kasei Microdevices or AKM. AKM is a Japanese maker of semiconductor devices for the consumer, automotive and industrial market, and is known for technology leadership in the analog space. Atomera is particularly pleased to have AKM as our first licensee, since we have worked with them for several years and they have an exceptionally deep understanding of how MST can benefit their products.
AKM has executed in integration license with us, meaning they have paid us for the right to integrate our technology on their way first. Our licenses have three stages: integration, manufacturing and distribution. I'll provide more detail on the structure of our licenses later in my comments.
On October 2, we were able to announce our second commercial integration license with STMicroelectronics, one of the world's largest semiconductor companies with annual revenue over $8 billion. ST is a leading European provider of semiconductor solutions across many markets, but principally in the areas of smart driving and the Internet of things. This license with ST shows how quickly a customer can adopt our technology since it took less than two years from our -- the start of our work with them until they signed up for a license.
In our view, until an IP licensing business successfully charges customers to license their technology, they are still in the development phase. With the completion of our first two revenue bearing license agreements, Atomera has officially entered our commercial phase. And we will continue working aggressively to sign new license fees and move our customers into volume production.
We have been speaking about our model of upfront license fees and production royalties for some time, and these first two agreements validate the acceptability of our model to the industry. It is important to understand that customers do not sign a license agreement casually. In both cases, these investments in MST had to go to a very senior level of management, accompanied by a plan or how they would ultimately take this technology to production before receiving approval for license execution.
On October 15, we closed the public offering of 2.625 million shares of common stock that resulted in us raising approximately $11.5 million after fees and expenses. As a result of the offering, we have now successfully strengthened our balance sheet and positioned the company such that if we continue to execute our business plan, we will not need to return to the capital market. We expect to use the proceeds from the offering to support customer integration of MST with outsource spending on deposition and testing, as well as additional engineering headcount.
In addition to the license and financing activities, our work with customers has continue to progress very nicely. As a review, Atomera represents customer activity with the phases of engagement shown here on Slide 6. Phase 1 includes customers under NDA who are planning an evaluation of our technology. In Phase 2, we deposit our MST film on customer's wafers and conduct physical characterization. Phase 3 is where customers in corporate MST during the production of their wafers and use the test results to justify licensing our technology. It is generally in Phase 3 that we are most likely to sign license agreement with customers. In fact, our engagements to both AKM and ST are in Phase 3. Phases 4 and 5 are where customers install our technology in their fab and transition to production.
I'm pleased to share with you that during the last three months, Atomera has added 2 new customers and engagements to our pipeline. One additional engagement is now in Phase 1, and we have added two new engagements to Phase 2. With these additions, today we have 20 engagements underway with 16 different customers and 11 engagements during that critical third integration phase. Four customers continue to work with us on multiple notes or technologies simultaneously.
