Gross loss was $1.5 million for the six months ended June 30, 2021 compared to a profit of $1.6 million for the three and six months ended June 30, 2020. The gross loss for the six months ended June 30, 2021 was due primarily to lower absorption of overhead costs as a result of overall lower revenues.
Combined general and administrative, selling and marketing, and research and development expenses for the three months ended June 30, 2021 increased to $31.0 million, compared to $13.7 million for the three months ended June 30, 2020. The net increase in total operating expenses of $17.3 million included a $5.0 million increase in stock-based compensation further described below, $6.0 million increase in salaries and related employee costs related to personnel growth, and $5.1 million increase in materials and services.
Combined general and administrative, selling and marketing, and research and development expenses for the six months ended June 30, 2021 increased to $74.9 million, compared to $27.3 million for the six months ended June 30, 2020. The net increase in total operating expenses of $47.6 million included a $28.2 million increase in stock-based compensation further described below, $10.1 million increase in salaries and related employee costs related to personnel growth, and $7.4 million increase in materials and services.
The increase in stock-based compensation from three and six months ended June 30, 2020 to the three and six months ended June 30, 2021 is primarily due to the revaluation of restricted stock awards that are treated as a liability as discussed in Notes 7 and 9 of Berkshire Grey’s Consolidated Financial Statements. For other stock-based awards, stock-based compensation included in operating expenses increased by $0.9 million and $1.6 million for the three and six months ended June 30, 2021 as compared to the three and six months ended June 30, 2020.
Net losses were $31.8 million for the three months ended June 30, 2021 compared to $9.7 million for the three months ended June 30, 2020. The increase in net losses was primarily due to the increase in stock-based compensation expense and increases in operating expenses.
Net losses were $76.4 million for the six months ended June 30, 2021 compared to $21.4 million for the six months ended June 30, 2020. The increase in net losses was primarily due to the completion, and recognition of revenue, of a $22.3 million customer contract in the first quarter of 2020, the increase in stock-based compensation expense, and increases in operating expenses. six months ended June 30, 2021
Results of Operations
The following is a description of significant components of our operations, including significant trends and uncertainties that we believe are important to an understanding of our business and results of operations.
Comparison of the three and six months ended June 30, 2021 and 2020
Revenue
Berkshire Grey generates revenue through the sale, delivery, installation of customer contracts in the United States and Japan. The following table presents revenue as well as the change from the prior period.
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| | For the Three Months Ended June 30, | | | | | | For the Six Months Ended June 30, | | | | |
(Dollars in thousands) | | 2021 | | | 2020 | | | Change | | | 2021 | | | 2020 | | | Change | |
Revenue | | $ | 4,503 | | | $ | 2,752 | | | $ | 1,751 | | | | 64 | % | | $ | 8,468 | | | $ | 29,028 | | | $ | (20,560 | ) | | | (71 | )% |
Total revenue for the three months ended June 30, 2021 and 2020 was $4.5 million and $2.8 million, respectively, an increase of $1.7 million or 64%. The increase is related to additional customer deployment activities.
Total revenue for the six months ended June 30, 2021 and 2020 was $8.5 million and $29.0 million, respectively, a decrease of $20.5 million or 71%. The decrease is primarily due to the completion of a $22.3 million customer contract for which revenue was recognized at a point in time in the first quarter of 2020, whereas revenue during the first half of 2021 was generated from incremental development and deployment of customer contracts in which revenue is recognized on a percentage of completion basis, and the sale, delivery, installation and/or completion of contracts with existing customers. Our revenue can fluctuate significantly from quarter to quarter depending on the number of projects in process and the method of accounting used to recognize revenues.
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