This data-set was collected as part of two validation activities. The first is an experimental validation of a Jacobian analysis. The second is the experimental validation of a Jacobian-based stiffness analysis for parallel manipulators with two end-effectors and non-redundant legs. Measurements have been performed over the workspace of a passive spatial 2-DoF mechanism with two end-effectors. The mechanism has two RRR legs and one RRRR leg, which are connected to the base and where each second revolute joint was implemented as a compliant joint. In addition two RRR chains internally connect the two end-effectors and the terminal links of the three legs. The dataset is stored as a tab-delimited ASCII file. The dataset consists of 6-D wrench measurements on both the first end-effector (EE1) and the second end-effector (EE2). As such, the resulting 12-dimensional measurement vectors contain the moment components m_{x,EE1}, m_{y,EE1}, m_{z,EE1}, the force components f_{x,EE1}, f_{y,EE1}, f_{z,EE1}, the …