  Nowadays, patenting activities are essential in converting applied science to
technology in the prevailing innovation model. To gain strategic advantages in
the technological competitions between regions, nations need to leverage the
investments of public and private funds to diversify over all technologies or
specialize in a small number of technologies. In this paper, we investigated
who the leaders are at the regional and assignee levels, how they attained
their leadership positions, and whether they adopted diversification or
specialization strategies, using a dataset of 176,193 patent records on
graphene between 1986 and 2017 downloaded from Derwent Innovation. By applying
a co-clustering method to the IPC subclasses in the patents and using a z-score
method to extract keywords from their titles and abstracts, we identified seven
graphene technology areas emerging in the sequence synthesis - composites -
sensors - devices - catalyst - batteries - water treatment. We then examined
the top regions in their investment preferences and their changes in rankings
over time and found that they invested in all seven technology areas. In
contrast, at the assignee level, some were diversified while others were
specialized. We found that large entities diversified their portfolios across
multiple technology areas, while small entities specialized around their core
competencies. In addition, we found that universities had higher entropy values
than corporations on average, leading us to the hypothesis that corporations
file, buy, or sell patents to enable product development. In contrast,
universities focus only on licensing their patents. We validated this
hypothesis through an aggregate analysis of reassignment and licensing and a
more detailed analysis of three case studies - SAMSUNG, RICE UNIVERSITY, and
DYSON.
