Thomas Durkin
Analyst · KBW
Thank you, David, and good morning, everyone. As David mentioned, we grew adjusted book value by approximately 12% during the quarter to $16.45 per share from $14.72 per share last quarter. We grew the portfolio from $2 billion to $2.2 billion, while decreasing our economic leverage ratio from 2.2x to 1.8x. During the quarter, we doubled our liquidity to over $143 million of cash in unencumbered Agency MBS. We will walk you through our robust pipeline and how we see the company rapidly deploying this fresh capital.
To dig a bit deeper into the company's activity, we are active in purchasing approximately $610 million of non-agency loans. Our mortgage affiliate Arc Home also hit record production within its non-agency channel during the third quarter, which Nick will walk through in more detail later in the call. During the month of October, the company continued its robust acquisition pace by purchasing an additional $386 million of loans, demonstrating the consistency in our pipeline of assets to support MITT's growth.
As previously disclosed, both legacy commercial loans that were on our books heading into the third quarter were paid off at par. Those proceeds, combined with our previously disclosed sale of CMBS earlier in the quarter, generated net proceeds of over $63 million for reinvestment. As David mentioned, but it bears repeating, MITT has no remaining commercial exposure, and we are now fully focused on building our residential loan portfolio.
During the quarter, we further reduced our exposure to Agency MBS as we thought the basis had reached a point where further tightening was unlikely and also sold our remaining excess MSR portfolio. Further strengthening our liquidity position, we also generated proceeds just shy of $30 million from a large accretive sale of our legacy RPL and NPL whole loans, which we provide more details on later in the presentation.
Moving on to our financing and capital activity during the quarter. We successfully completed another securitization during August, which -- and we provide more details on this transaction later in the deck. As I've previously stated on past earnings call, we are committed to being very disciplined with regards to the pacing of our securitizations to derisk our warehouse lines. Given our expanding investment pipeline and in an effort to provide flexibility, during the quarter, we increased our borrowing capacity for non-QM products to $1.1 billion and added $500 million of borrowing capacity to finance GSE nonowner-occupied loans.
Notably, this quarter, we were active in using the capacity under our existing share repurchase program. In aggregate, we repurchased approximately 260,000 shares at a weighted average price of $11 even, a price well below our book value, deploying approximately $2.8 million of the company's excess liquidity. The company has approximately $11.8 million of additional capacity left under the current buyback plan, and we'll continue to evaluate repurchases to the extent it is accretive to our balance sheet.
Turning to Slide 7. We felt it was important to take some additional time to walk investors through this visual of what was a particularly active and important quarter in MITT's repositioning to a pure-play residential mortgage credit REIT. We began the quarter with $71 million of liquidity. Securitization proceeds in excess of warehouse lines created an additional $30 million. The par payoff of our remaining CRE loans and sales of CMBS created an additional $63 million of net proceeds. The sale of reperforming and nonperforming loans generated $29 million. And rounding it out was another $6.8 million from agency sales. We effectively deployed this liquidity during the quarter to invest $58 million net of financing into non-QM loans, invest another $16 million net of financing into GSE nonowner-occupied loans, repurchased $2.8 million of common shares, again at a weighted average price of $11 and paid common and preferred dividends in aggregate of $8.9 million.
So in summary, during the quarter, we were able to double our liquidity, successfully exiting our noncore business lines at a profit, providing the company with ample firepower to continue deployment within the residential whole loan space. Subsequent to quarter end, we have deployed $48 million of liquidity into new whole loan investments, leaving us with $91 million of liquidity as of October 31.
On the next slide, we wanted to show the remarkable progress made since our fourth quarter earnings call when we began making the transition to a pure-play residential credit REIT, and our portfolio composition has only continued to shift more towards non-agency loans as a result of our October purchases. During the first 3 quarters of 2021, we achieved substantial growth in MITT's investment portfolio and adjusted book value per share from $1.4 billion and $11.81 per share to $2.2 billion and $16.45 per share, respectively. This portfolio growth was led by strong loan acquisition channels resulting in $1.3 billion of gross residential purchases during the year and further volume growth at our operating partner, Arc Home.
During the year, we were patient in exiting legacy noncore assets at the opportune time in order to maximize proceeds and profits for our investors. While we are pleased with the progress that has been made year-to-date, what really drives our strong convictions in our business model is the growing pipeline of opportunities we see and future potential earnings power growth, this shift provides our investors, which brings us to the next slide.
We have spent a lot of time formulating our plan for MITT's future, particularly in light of all the team's accomplishments year-to-date in simplifying the business and growing our whole loan portfolio, enabling the company to reposition to its new focused strategy. This slide illustrates the compelling investment opportunity we see in MITT by highlighting how we expect to unlock the embedded earnings power of MITT's equity by redeploying it into our new strategy. At a high level, we believe we can create retained investments post securitization at loss adjusted ROEs of 14% to 18%.
Further, we've seen the returns play out through our most recent securitization. And despite all the progress that has been made year-to-date, we still see approximately 40% of our equity base available to be rotated into our securitization strategy, which should further drive earnings power.
Away from the investment portfolio, we will still be proactive in addressing our balance sheet optimization, including through further repurchases of our common shares at discounts and continuing to work with our preferred shareholders on exchanges that make sense for both parties.
With that, I'll turn the call over to Nick to further discuss our portfolio in Arc Home.