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Abstract The objective of the paper is to retrospectively analyze the suction pile design methodologies based on suction pile installations recently carried out offshore East India, at water depths ranging from 380 m to 805 m. The scope of the study includes evaluating horizontal holding capacity, self-penetration, suction pressure, retrieval pressure, penetration, and retrieval rates of the installed suction piles in very soft clay. Challenges associated with deepwater suction pile installation are also discussed briefly in this paper. The ultimate capacity of the suction piles was initially estimated using limit equilibrium approaches based on the works of Randolph et al. (1998), Taiebat & Carter (2005). A more detailed verification was subsequently carried out using finite element analysis. Monitoring data from the installation of suction piles were evaluated against these predictions. Soil sensitivity values (remoulding effect) of 2 to 3 were considered for self-penetration prediction across the site. The suction pile installations were completed smoothly. Field installation data indicate that many of the actual suction pile self-penetration values fall between the low and high estimate ranges. The maximum suction pressures observed during the installation were within the predicted values. A Self-penetration rate between 0.10 m/min and 0.9 m/min was observed, considering ~0.7% top vent hatch opening and gradual release of tension. The over-pressure required for the suction pile retrieval increased by up to 60% compared to the installation suction pressure, accounting for a setup time between 10 and 94 days and the application of constant tension. All minimum lateral holding capacity requirements were successfully met, as demonstrated by the actual pipeline initiation operations, confirming the reliability of the analytical approach. The paper discusses the installation experiences of thirty-five suction piles in deep water clay. The field data and analysis methods undertaken in this study enhance the reliability of future design and installation predictions, particularly for this site and other locations with similar soil conditions. The marine operations and monitoring procedures that address challenges associated with deepwater installation are briefly presented, providing useful insights for future installations.