4. Acquired Technology

Acquired technology consisted of the following (in thousands):

The Company recognized amortization expense of $0.5 million and $0.1 million for the nine months ended September 30, 2020 and 2019, respectively.  The Company expects to recognize $0.2 million of amortization expense for the remaining three months of 2020, $0.6 million annually in the years ended December 31, 2021 through 2023, and $0.4 million in 2024. The weighted‑average remaining amortization period is 3.8 years.