The uniform B-spline surface patch is constructed as a Cartesian product of two uniform B-spline curves. The biquadratic B-spline surface patch. For example is fully defined by nine control points is given as,

$P(u, v)=\left(\frac{1}{2}\right)^{2}\left[\begin{array}{lll}{u^{2}} & {u} & {1}\end{array}\right]\left[\begin{array}{ccc}{1} & {-2} & {1} \\ {-2} & {2} & {0} \\ {1} & {1} & {0}\end{array}\right]\left[\begin{array}{ccc}{P_{00}} & {P_{01}} & {P_{02}} \\ {P_{10}} & {P_{11}} & {P_{12}} \\ {P_{20}} & {P_{21}} & {P_{22}}\end{array}\right]\left[\begin{array}{ccc}{1} & {-2} & {1} \\ {-2} & {2} & {0} \\ {1} & {1} & {0}\end{array}\right]\left[\begin{array}{c}{v^{2}} \\ {v} \\ {1}\end{array}\right]$