  Semantic Overlap Summarization (SOS) is a constrained multi-document
summarization task, where the constraint is to capture the common/overlapping
information between two alternative narratives. While recent advancements in
Large Language Models (LLMs) have achieved superior performance in numerous
summarization tasks, a benchmarking study of the SOS task using LLMs is yet to
be performed. As LLMs' responses are sensitive to slight variations in prompt
design, a major challenge in conducting such a benchmarking study is to
systematically explore a variety of prompts before drawing a reliable
conclusion. Fortunately, very recently, the TELeR taxonomy has been proposed
which can be used to design and explore various prompts for LLMs. Using this
TELeR taxonomy and 15 popular LLMs, this paper comprehensively evaluates LLMs
on the SOS Task, assessing their ability to summarize overlapping information
from multiple alternative narratives. For evaluation, we report
well-established metrics like ROUGE, BERTscore, and SEM-F1$ on two different
datasets of alternative narratives. We conclude the paper by analyzing the
strengths and limitations of various LLMs in terms of their capabilities in
capturing overlapping information The code and datasets used to conduct this
study are available at https://anonymous.4open.science/r/llm_eval-E16D.
