Thank you, Michael.
On Page 4, we have presented the company's key metrics for the first quarter 2020 compared to the prior year period.
Net loss before noncontrolling interests for the quarter was $60.6 million, a decrease of $64.9 million over the prior year. The decrease was primarily driven by unrealized losses on our investment in Invesque as well as other equities, reflecting the disruption in global markets as a result of the COVID-19 pandemic. Excluding investment gains and losses, revenues were up 18.7%, driven by improvements in Tiptree Insurance top line results, including the addition of Smart AutoCare. Operating EBITDA for the quarter was $15.8 million, up 25% from the prior year due to growth in insurance operations as well as positive contributions from Tiptree Capital driven primarily by a full quarter of shipping operations with all 5 vessels under management.
On the bottom of the page, we show a walk from operating EBITDA to total pretax income, highlighting the key differences between the 2 metrics. Book value per share decreased to $9.73, driven by the net loss mentioned earlier. Despite the decline in book value, we believe that we maintained sufficient capital and liquidity to support our business. At quarter end, cash and cash equivalents were $108.8 million, $84 million of which is held outside the statutory insurance entities.
Turning to Page 5, we highlight our capital allocated between Tiptree Insurance and Tiptree Capital, along with their respective returns, to insist -- to assist investors in understanding Tiptree's enterprise value. When considering capital allocation decisions, we look at total capital, which includes corporate debt held at both the holding company and at our insurance subsidiaries. In February, we extended the maturity and upsized our corporate credit facility with a new $125 million 5-year borrowing.
We evaluate our return on capital using operating EBITDA, to which the latest 12-month period was $66.9 million, up 14.2% from the latest 12-month period ending Q1 2019. Our total return of approximately 9.7% is driven by a 13.2% return in Tiptree Insurance and a 13.4% return in Tiptree Capital. The key drivers for the period were growth in insurance underwriting income and fee revenues across all product lines, including contributions from Smart AutoCare for the first quarter of 2020; positive contributions from shipping and mortgage operations in Tiptree Capital; and relatively stable corporate expenses. The most recent 12-month period included approximately $12 million of dividends from our holdings of Invesque. Our earnings from Tiptree Capital [ will leave ] the benefit of approximately $2.5 million of earnings per quarter, while Invesque dividend is suspend.
With that, let's turn to Tiptree Insurance results for the quarter. On Page 7, we highlight our underwriting performance and then, on the following page, returns from the investment portfolio.
We continue to see positive top line growth across our product lines. Gross written premiums were $277 million, up 40%. Net written premiums grew by $11.5 million, driven by growth in warranty and specialty programs. Underwriting margin was up $9.6 million or 29.5%. And our combined ratio held steady at 93.3%, demonstrating our ability to continue to grow profitably in our insurance business. Unearned premiums and deferred revenue on the balance sheet stand at over $1 billion at the end of the quarter, up 55.5% from this time last year, including $158 million from Smart AutoCare. While we expect to see a slowing in this growth trajectory in Q2 as the economies reopen in the U.S. and Europe, we expect to slowly return to normalized growth rates in the second half of the year.
Turning to the investment portfolio on Page 8. Our net investments grew by $67 million year-over-year, up 14.4%, driven by growth in net written premiums. $407 million of the portfolio or 76% is held in liquid, highly rated fixed income securities. The average rating on that portion of the portfolio is AA, which we believe should continue to provide sufficient support to our claims paying ability despite the current volatile market. Net investment income for the quarter was $3.5 million, down $0.8 million, as we reduced our exposure to levered corporate credit, combined with an overall decline in interest rates. Despite decline -- the decline in income, we believe that the portfolio benefits created by the stability in our fixed income portfolio as a result of these moves more than offsets the short-term loss of income. We ended the quarter with $19 million of cash available for reinvestment in the portfolio.
Net portfolio loss was $29.7 million, down approximately $39 million versus the prior year period, driven by unrealized and realized losses of $33.6 million on equities and other securities in the portfolio, $10.2 million of which was related to Invesque. The unrealized losses were primarily driven by the financial market disruptions related to the economic impacts from COVID-19.
On Page 10, we present the results of Tiptree Capital, which today consists of our Invesque shares, shipping and mortgage operations. Over time, we would expect that our investments could shift as we recognize returns in one asset class or business and reinvest in others. For the quarter, the pretax loss was the result of unrealized losses on our Invesque shares. At the end of the quarter, our Invesque investment held in Tiptree Capital was $45 million. The remaining $9 million is held in our insurance portfolio.
For the quarter, operating EBITDA in Tiptree Capital increased to $6.1 million, primarily driven by a full quarter of operations from the vessels purchased in 2019 in our maritime shipping business.
Now let me return the call back to Michael to conclude our prepared remarks.