Citation Tracker provides patent citation intelligence to answer critical IP strategy questions: "Who is citing our portfolio?", "What prior art do we depend on?", and "Which competitors are encroaching on our technology space?" The interface uses a shared Scope card to define a portfolio and time window, then refreshes four analytics widgets in parallel: Forward-Citation Impact, Dependency Matrix, Risk Radar, and Encroachment.
Citation analysis reveals relationships between patents/publications that keyword search alone may not expose. When a patent examiner or applicant cites prior art, that citation establishes a formal link indicating technological relevance, potential blocking relationships, or design-around requirements. Citation Tracker transforms this citation network into actionable intelligence:
The Scope card defines portfolio and analysis parameters that are applied across four widgets:
Select how to define the patent portfolio under analysis. Three modes are available:
Source Assignee(s), Patent/Publication Numbers, or Search Filters
Constrain analysis to citations within a specific date range. The date filters apply to the citing patent's publication date, not the cited patent.
Example: From 2023-01-01, To 2025-06-30
Optionally specify target assignee(s) to focus Risk Radar and Encroachment analysis on citations from those specific entities.
Examples: 'Apple', 'Amazon', 'Meta Platforms'
Forward-Citation Impact quantifies the influence and market relevance of a source assignee's portfolio by analyzing which patents cite the source assignee's patents/publications. Patents with high forward citation counts tend to represent foundational innovations that shape subsequent R&D directions. This section helps identify the most influential IP and track how that influence evolves over time.
The Dependency Matrix visualizes citation relationships between assignees to expose technology dependencies, potential licensing relationships, and competitive dynamics. Frequent citations from one assignee to another may suggest freedom-to-operate, infringement, licensing, or other strategic implications.
Risk Radar ranks patents in a source assignee's portfolio by strategic risk, combining two complementary signals: Exposure (external pressure from other assignees' citations) and Fragility (internal structural weakness in the prior art foundation). The resulting Overall Risk Score provides a single, sortable metric for prioritizing legal review, design-around analysis, and portfolio management decisions.
What it measures: Exposure Score quantifies the relevancy of a particular patent (using number and velocity of forward citations as a proxy). A patent with many forward citations is more likely to be the subject of post-grant procedures (e.g., inter partes review).
Implies: Industry/technology relevance and/or de facto standard; significantly important to another assignee's patent(s).
Why it's included: Exposure Score is frequently a primary indicator in relation to infringement risk, competitor monitoring, strategic licensing/defensive considerations, and identifying patents that are likely to influence future filings.
Exposure combines normalized forward citation volume with other assignee citation ratio:
norm_total = log-scaled forward citation count (calibrated against corpus 95th percentile)comp_ratio = forward citations from other assignees / total forward citationsExposure = 70 × norm_total + 30 × comp_ratio
The 70/30 weighting reflects the historical trend that absolute citation volume explains variance to a more significant degree than other assignee citation ratio, while other assignee ratio provides directional sensitivity.
What it measures: Fragility Score measures how narrow, clustered, or homogeneous the cited prior art is for a patent. A patent is considered "fragile" when a small, concentrated slice of prior art supports it. For example, a patent that disproportionately cites prior art in a single CPC technology area or a small set of assignees is more likely to have a meaingfully narrower claim scope and/or a less robus detailed description.
Implies: Vulnerabilities to invalidation attacks (e.g., not sufficiently enabling, etc.); relatively less difficult to design around.
Why it's included: From a legal/portfolio perspective, fragility matters because concentrated CPC prior art indicates a narrow conceptual base that's easier to design around. Low assignee diversity means high dependence on a small set of references that are easier to attack. This provides insight into invalidity risk, lower commercial value, and relatively lower likelihood of patent robustness.
Contraindications: Concentrated CPC prior art and/or little to no citations to other assignees can indicate seminal or highly innovative subject matter, which may not necessarily imply fragility.
Fragility combines CPC concentration with assignee diversity:
cpc_top_share = fraction of backward citations in the dominant CPC codeassignee_diversity = 1 − (top assignee share of backward citations)Fragility = 60 × cpc_top_share + 40 × (1 − assignee_diversity)
CPC concentration is generally a stronger predictor of narrow prior art scope than assignee diversity; accordingly, cpc concentration is given greater weight than assignee diversity.
What it measures: Overall Risk Score blends Exposure (external pressure from other assignees) and Fragility (internal robustness/weakness) to estimate the strategic risk associated with a patent.
Implies: Patent strength and robustness; coarse metric for forecasting ROI.
Why it's included: A single, sortable metric is useful to for flagging patents that are high-risk and/or high-attention. Flags may serve as preliminary separation criteria for pruning/licensing/divestiture decisions, for example, by highlighting patents that are weakly supported or have low potential ROI. This is a portfolio prioritization heuristic.
Overall = 55 × (Exposure / 100) + 45 × (Fragility / 100)
The 55/45 weighting slightly prioritizes Exposure because it is generally a more consistent metric than Fragility.
Each score captures a distinct dimension of risk, and a more comprehensive view is derived from the aggregate:
| Score | Measures | Type of Risk | Relevance | Significance |
|---|---|---|---|---|
| Exposure | Other assignees' forward citations | External pressure | FTO, litigation | Predicts infringement/competition risk |
| Fragility | Prior-art diversity & narrowness | Internal structural weakness | Prosecution, IP counsel | Predicts invalidity/design-around vulnerability |
| Overall | Weighted blend | Vulnerabilities and risks | IP portfolio management | Sort/prioritize IP assets |
Aggregate Implications: What patents are highly relevant to some or one other assignee(s), which patents are estimated to be sunk costs now, where should future AI/ML IP investments be directed.
Encroachment analysis tracks how target assignees are citing patents/publications held by a source assignee over time. When a target assignee's patent cites a source assignee's patent/publication, there is an implication of relevancy in a technology space. Monitoring encroachment trends may assist in early identification of licensing potential, technology areas of increasing value, and/or potential infringement actions.
Please note that citation data for the patents and publications available in the SynapseIP database may be incomplete. For clarity and relevancy, cited patents and publications filed prior to 2007 (approximately) may be absent. Backward citations are currently available only for patents. Contact support@phaethon.llc to request extension of this feature to publications. Additionally, foreign references and non-patent literature are excluded at this time. As set forth in the SynapseIP Terms of Service, no express or implied warranties are made regarding the completeness of the available dataset.