> For the complete documentation index, see [llms.txt](https://wpahelp.windhamlabs.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wpahelp.windhamlabs.com/overlays.md).

# Overlays

Instruments flagged as **Overlay** in the *Define Portfolios* screen are not included when calculating the sum of weights constraint during optimization. 

![Classifying instruments as Overlays](/files/-MEyZmTDIZhOIv5CfUxn)

Some examples of overlay instruments are options, futures, swaps, and other derivative risk management instruments. We assume that these instruments do not require capital unlike instruments in the cash markets.