Managing External Innovation: The Case of Platform Extensions

After the list was created another round was conducted to filter out any result that does
not fit within the extension definition (see section 2.2.1). To decide which platform to
discard, the researcher examined the different sections on the platform website (like
developers guide, community, how to contribute, press release and other) and other
available resources from the literature.
Step 2:
The platform website was examined to determine if the platform was made extensible
between the period of January 2000 and June 2009. Platform website sections “home”,
“about”, “history”, “frequently asked questions”, “press releases”, and mail archives were
used to draw this information. A list of eligible extensible software platforms was
produced to be part of the sample.
3.3.4 Select waves of software platform cases
Cases were selected in three waves and Table 5 shows the 12 cases that were included in
the sample and selected cases for each wave. For the first and second waves, four cases
were chosen randomly from the refined list of software platforms that was produced in
step 3. Eisenhardt (1989) suggests using theoretical sampling when selecting cases for
case study research which implies that cases may be chosen to replicate previous cases or
extend emergent theory. For this study, previous research did not provide a reference to
select the cases using theoretical sampling as suggested by Eisenhardt (1989). When data
from the first two waves was collected and preliminary results emerged, a third wave of
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