Hi LungDoc,
Yes, you can create as many different *.mm4 portfolio files as you want. See "File / Save Portfolio As...". However, this is not the recommended or usually the best way to use portfolios. It usually works better to just have a single *.mm4 file, and use sub-portfolios. In your example, you can create a Portfolio A and Portfolio B under your current Master Portfolio, and then put whatever you want in each. You can have as much hierarchy in sub-portfolios as you want. The benefit to using only a single *.mm4 portfolio file is that you only have one data file, and you can operate on all your data at the same time. For example, when retrieving prices, you can update everything with a single retrieve. For more help on setting up and working with sub-portfolios, see our
Sub-Portfolio Tutorial.