<svg xmlns="http://www.w3.org/2000/svg">
<clipPath id="clip2">
  <rect width="150" height="150"/>
</clipPath>
<clipPath id="clip1">
  <rect x="50" y="50" width="150" height="150"/>
</clipPath>
<g clip-path="url(#clip1)">
  <rect width="200" height="200" fill="green" clip-path="url(#clip2)"/>
</g>
</svg>