In GeneSpring, currently it is not possible to merge multiple experiments to create a single experiment.
Create another experiment using all these 150 samples from three different experiment by selecting the Choose Samples option in the data loading step.
Note: Once the data files are imported into GeneSpring GX to create an experiment, the data files are converted into samples and would be stored in the database. If the Choose files option is selected again, then the sample is created the second time which utilizes twice the space in the database.
Sample probe profile file in GeneSpring export format will be supported by GeneSpring.