Ribbon Communications Inc.

RBBN

Ribbon Communications Inc. provides communications technology in the United States, Europe, the Middle East, Africa, the Asia Pacific, and internationally. It operates through two segments, Cloud and Edge, and IP Optical Networks. The Cloud and Edge segment provides software and hardware products, solutions, and services for voice over internet protocol communications, voice over long-term evolution, and voice over 5G communications, and unified communications and collaboration.

About the company

Country: United StatesPrice: $1.47Market Cap: $263.4M

Investment snapshot

12%positive consensus

Scored 1d ago

Positive

BUY / PASS

Neutral / negative

5 / 9

NEUTRAL / FAIL

Median fair value

$1.87

+27.2% vs price

Models with upside

3 / 17

Positive margin of safety

Strongest signal

RBBN undervalued: all 3 models price fair value above $1.47 (median $1.87)

Key risk

No clean pass — all 8 investors flag at least one growth criterion

Framework analysis

Verdict	Meaning
BUY	Positive purchase signal: the framework's buy requirements are met.
PASS	The company clears the framework's checklist or screen, but the framework does not produce a buy signal. For valuation frameworks this often means margin of safety is missing, insufficient, or unavailable; some screen-only frameworks have no intrinsic-value BUY state.
NEUTRAL	Neither a positive nor negative conclusion. It does not mean to hold an existing position.
FAIL	The company does not clear the framework's requirements.
Ranked	Ranked strategies do not use PASS: selected cohort is BUY, outside the cohort is FAIL, and unranked is NEUTRAL.

Current investor scores use trailing 12-month flows and the latest balance sheet where supported. Multi-year and EPS tests retain annual history; each framework shows its financial basis below. Intrinsic values use annual financials.

Metric	Graham Defensive Value	Buffett Quality Compounder	Lynch GARP	Greenblatt Magic Formula	Piotroski F-Score	Dreman Contrarian Value	Munger Quality Focus	Pabrai Dhandho Framework	Akre Three-Legged Stool	Marks Risk-Aware Value	Ackman Activist Value	Templeton Global Bargain Hunter	Sleep Scale Economies Shared	Asness Systematic Factors	Neff Low-P/E Total Return	Schloss Asset-Value Discipline	O'Shaughnessy Systematic Factor Composite
Verdict	FAIL	FAIL	FAIL	FAIL · Rank #2137 (Top 69%)	NEUTRAL	FAIL	PASS	NEUTRAL	FAIL	FAIL	PASS	NEUTRAL	NEUTRAL	FAIL	FAIL	FAIL	NEUTRAL
Score
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Intrinsic Value (annual)		N/A	N/A	N/A	N/A	N/A		N/A	N/A	N/A		N/A	N/A	N/A	N/A	N/A	N/A
Margin of Safety	+58.7%	N/A	N/A	N/A	N/A	N/A	+5.8%	N/A	N/A	N/A	+21.4%	N/A	N/A	N/A	N/A	N/A	N/A
Financial Basis	TTM ended 2026-09-30 · Balance sheet at 2026-09-30 · Annual history · FY 2025 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 Latest source filing: 2026-02-26 Score computed: 2026-11-14	Annual history · FY 2025 · Balance sheet at 2026-09-30 · TTM ended 2026-09-30 vs 2025-09-30 · TTM ended 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	TTM ended 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 Latest source filing: 2026-02-26 Score computed: 2026-11-14	Annual history · FY 2025 · TTM ended 2026-09-30 · Balance sheet at 2026-09-30 · Market data at 2026-11-01 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Qualitative assessment · Annual history · FY 2025 · TTM ended 2026-09-30 · Balance sheet at 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Qualitative assessment · Annual history · FY 2025 Latest source filing: 2026-02-26 Score computed: 2026-11-14	Annual history · FY 2025 · Qualitative assessment · TTM ended 2026-09-30 · Balance sheet at 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 · Qualitative assessment Latest source filing: 2026-02-26 Score computed: 2026-11-14	Annual history · FY 2025 · TTM ended 2026-09-30 · Balance sheet at 2026-09-30 · Market data at 2026-11-01 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 · Price history 2025-01-01–2026-11-01 · Balance sheet at 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 · Qualitative assessment Latest source filing: 2026-02-26 Score computed: 2026-11-14	TTM ended 2026-09-30 · Balance sheet at 2026-09-30 · Price history 2025-01-01–2026-11-01 · Annual history · FY 2025 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 · TTM ended 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	Annual history · FY 2025 · Balance sheet at 2026-09-30 Latest source filing: 2026-10-28 Score computed: 2026-11-14	TTM ended 2026-09-30 · Annual history · FY 2025 · Price history 2025-01-01–2026-11-01 Latest source filing: 2026-10-28 Score computed: 2026-11-14

Where It Passes

Valuation models100% pass✓ 3▾
RBBN undervalued: all 3 models price fair value above $1.47 (median $1.87)
Graham fair value$3.56
✓Graham+58.7% margin vs $1.47
Munger fair value$1.56
✓Munger+5.8% margin vs $1.47
Ackman fair value$1.87
✓Ackman+21.4% margin vs $1.47

Where It Falls Short

Growth0% pass✓ 2✗ 11▾
No clean pass — all 8 investors flag at least one growth criterion
EPS Growth (3-yr avg, 10-yr window)
✗Graham>= 33% growth
Basic earnings-growth PEG (dividends excluded)P/E 6.7x (growth N/A)
✗Lynch< 1.0 (ideally < 0.5)
3-5 Year EPS CAGR-18.5%
✗Lynch15-30% (Fast Grower); > 0% to pass
Inventory Growth vs Revenue GrowthInv: 8.0% vs Rev: -7.8%
✗LynchInventory growth < Revenue growth
EPS Growth Direction
✗DremanPositive over recent years
EPS CAGR
✗Dreman> 5% annualized
Positive Net Income Frequency2/11 years positive
✗MarksPositive net income in >= 7 of last 10 years
3yr Median Revenue Growth0.9%
✗Ackman>= 5%
Positive EPS Growth Frequency4/5 years with positive EPS growth
✓AckmanPositive EPS growth in >= 3 of last 5 years
5-Year EPS CAGR
✗Templeton> 0% (5-year EPS CAGR)
Revenue growth vs. gross and operating margin trendgross margin 49.4% -> 49.8%, operating margin -2.9% -> -0.4%
✓SleepRevenue rising; gross margin flat or falling; operating margin holding
5-year Revenue CAGR0.0%
✗SleepCAGR > 7%
3-5 Year Diluted EPS CAGR-18.5% over 5 years
✗Neff7%-20% annualized
Efficiency0% pass✓ 1✗ 10▾
No clean pass — all 8 investors flag at least one efficiency criterion
Current Ratio1.32
✗Graham>= 2.0
ROIC (3-5 yr avg)-3.6%
✗Buffett> 10%
ROIC - WACC-13.6%
✗BuffettPositive (WACC = 10%)
EBIT / (NWC + Net Fixed Assets)-21.8%
✗Greenblatt> 25%
Current Ratio Change YoY1.41 -> 1.44
✓PiotroskiIncreased YoY
Revenue / Total Assets Change YoY0.72x -> 0.70x
✗PiotroskiImproved YoY
Current Assets / Current Liabilities1.32
✗Dreman> 1.5
Return on Invested Capital-3.2%
✗Munger> 15%
ROIC (high and growing)FY2023: ROIC=-2.8%; FY2024: ROIC=1.8%; FY2025: ROIC=-0.3%
✗AkreLatest 3 consecutive FYs: ROIC > 15% in each
Reinvestment Rate x ROIC-0.3% (RR=100% x ROIC=-0.3%)
✗AkreReinvestment Rate * ROIC > 10%
ROIC (5-year)0/5 years above 12% (latest -0.3%)
✗SleepROIC > 12% in a majority of years
Profitability13% pass✓ 8✗ 27▾
14 of 16 flag RBBN's profitability — Graham, Buffett, Lynch +11 more
Net income / market capitalization+7.06%; #1167/6340 (top 18.4%)
✓AsnessTop 30% of eligible cross-section✗OshaughnessyTop 10% of eligible cross-section
Positive EPS (10 years)2/12 years positive
✗GrahamPositive EPS every year for 10 years
EPS Growth (3-yr avg, 10-yr window)
✗Graham>= 33% growth
Net Income Positive (10+ years)2/12 years positive
✗BuffettPositive every year for 10+ years
ROE (up to 5-year arithmetic mean)-14.3%
✗Buffett> 15% arithmetic mean (app rule)
Operating Margin (10-yr trend)-0.4% (latest)
✓BuffettStable or rising over 10 years
Free Cash Flow Proxy
✗BuffettPositive and growing
Earnings Variance (10-yr CoV)
✗BuffettCoV < 0.3
Retained Earnings Effectiveness
✗Buffett$1 retained -> > $1 market value created
Basic earnings-growth PEG (dividends excluded)P/E 6.7x (growth N/A)
✗Lynch< 1.0 (ideally < 0.5)
3-5 Year EPS CAGR-18.5%
✗Lynch15-30% (Fast Grower); > 0% to pass
ROE4.8%
✗Lynch> 15%
EBIT / Enterprise Value-5.3%
✗Greenblatt> 10%
Earnings Yield + ROC AssessmentEY=-5.3%, ROC=-21.8%
✗GreenblattBoth EY > 10% and ROC > 25%
Net Income / Total Assets3.27%
✓PiotroskiROA > 0
ROA Change YoY-4.67% -> 3.27% (delta: +7.93%)
✓PiotroskiCurrent ROA > Prior ROA
(CFO / Total Assets) vs ROACFO/Assets=4.24%, ROA=3.27%
✓PiotroskiCFO/Assets > ROA
Gross Margin Change YoY52.7% -> 49.8%
✗PiotroskiImproved YoY
Pre-Tax Income / Revenue-8.9%
✗Dreman>= 8%
Net Income / Shareholders' Equity4.8%
✗Dreman> 12%
Margin of SafetyP/E=6.7x, P/B=0.6x
✓PabraiP/B < 1.5 or P/E < 15
Return on Equity-6.4% (3-yr avg)
✗AkreROE > 20% (3-year avg)
Discount to Intrinsic ValueN/A (negative normalized EPS)
✗Marks>= 20% below intrinsic value
Positive Net Income Frequency2/11 years positive
✗MarksPositive net income in >= 7 of last 10 years
Operating Income / Revenue-3.6%
✗Ackman>= 15%
Net Income / Shareholders Equity4.8%
✗Ackman>= 15%
5-Year EPS CAGR
✗Templeton> 0% (5-year EPS CAGR)
Operating Margin Trend-2.9% (2023) -> -0.4% (2025)
✓TempletonNon-negative operating-margin trend over 3 years
Revenue growth vs. gross and operating margin trendgross margin 49.4% -> 49.8%, operating margin -2.9% -> -0.4%
✓SleepRevenue rising; gross margin flat or falling; operating margin holding
Gross profit / total assets+33.60%; #1242/3702 (top 33.5%)
✗AsnessTop 30% of eligible cross-section
Net income / positive book equity+4.78%; #2484/5226 (top 47.5%)
✗AsnessTop 30% of eligible cross-section
Negative 5-year standard deviation of ROA-0.0532; #2650/5884 (top 45.0%)
✗AsnessTop 30% of eligible cross-section
3-5 Year Diluted EPS CAGR-18.5% over 5 years
✗Neff7%-20% annualized
Positive Diluted-EPS Years2/10 years positive
✗Schloss>= 70% positive over 5-10 observed years (app rule)
Verdicts17% pass✓ 2✗ 10▾
Split decision: 9 FAIL · 5 NEUTRAL · 2 PASS
Overall verdict
✗GrahamFAIL (2/9)✗BuffettFAIL (1/9)✗LynchFAIL (0/7)✗GreenblattRank #2137•PiotroskiNEUTRAL (F-Score 7)✗DremanFAIL (3/11)✓MungerPASS (2/4)•PabraiNEUTRAL (2/3)✗AkreFAIL (1/6)✗MarksFAIL (2/5)✓AckmanPASS (4/9)•TempletonNEUTRAL (6/8)•SleepNEUTRAL (4/6)✗AsnessFAIL (Rank #1255/2370 (Top 53.0%))✗NeffFAIL (2/6)✗SchlossFAIL (2/7)•OshaughnessyNEUTRAL (Not ranked)
Debt & Leverage25% pass✓ 4✗ 11▾
9 of 12 flag RBBN's debt & leverage — Graham, Buffett, Lynch +6 more
Total Debt / Shareholders' Equity0.84
✗Dreman< 0.8✓Templeton< 1.0 (fixed cap; proxy for below-sector-median leverage)✓SchlossD/E < 1.00x
LT Debt vs Net Current AssetsLT Debt $316.9M vs NCA $104.4M
✗GrahamLT Debt <= Net Current Assets
Debt/Equity & Interest CoverageD/E: 0.74, IC: -0.1x
✗BuffettD/E < 0.5 AND Interest Coverage > 5x
Total Debt / Equity0.84
✗Lynch< 0.33
Cash - Long-term Debt$-276.6M
✗LynchPositive preferred
LT Debt / Total Assets Change28.45% -> 26.77%
✓PiotroskiDecreased YoY
Current Assets / Current Liabilities1.32
✗Dreman> 1.5✗SchlossCurrent ratio >= 1.50x (app cutoff)
Debt Levels0.84
✗MungerDebt/Equity < 0.5✗AkreDebt/Equity < 0.3
Interest Coverage & Debt/EBITDAIC=-0.1x, D/EBITDA=N/A (D&A unavailable)
✗MarksInterest Coverage > 3x; Debt/EBITDA < 4x
Total Debt / Shareholders Equity0.84
✓Ackman<= 1.0
Negative debt-to-equity (higher means less debt)-0.8435; #3040/4210 (top 72.2%)
✗AsnessTop 30% of eligible cross-section
Valuation46% pass✓ 15✗ 13▾
7 of 13 flag RBBN's valuation — Graham, Lynch, Greenblatt +4 more
Net income / market capitalization+7.06%; #1167/6340 (top 18.4%)
✓AsnessTop 30% of eligible cross-section✗OshaughnessyTop 10% of eligible cross-section
Price / 3-yr avg EPS
✗Graham<= 15x
Price-to-Book Ratio0.6x
✓Graham<= 1.5x
P/E x P/B
✗Graham<= 22.5
Basic earnings-growth PEG (dividends excluded)P/E 6.7x (growth N/A)
✗Lynch< 1.0 (ideally < 0.5)
EBIT / Enterprise Value-5.3%
✗Greenblatt> 10%
Earnings Yield + ROC AssessmentEY=-5.3%, ROC=-21.8%
✗GreenblattBoth EY > 10% and ROC > 25%
Price / EPS6.7x
✓Dreman< 12x✓Templeton< 12x (fixed ceiling; proxy for the market's cheapest 40%)
Price / (CFO / Shares)5.0x
✓Dreman< 8x
Price / Book Value per Share0.6x
✓Dreman< 1.2x✓Templeton< 1.5x✓SchlossP/B <= 0.80x (app cutoff)
Valuation ReasonablenessP/E=6.7x
✓MungerP/E < 25 or Owner Earnings Yield > 5%
P/E or FCF YieldP/E=6.7x, FCF Yield=9.9%
✓PabraiP/E < 15 or FCF Yield > 10%
P/B or P/E vs. Historical AverageP/E=6.7x, P/B=0.6x
✓MarksP/E < 15 or P/B < 2.0
Discount to Intrinsic ValueN/A (negative normalized EPS)
✗Marks>= 20% below intrinsic value
Price / FCF per Share9.9x
✓Ackman<= 25
Price vs. Trailing Low100% of trailing low ($1.47)
✓Templeton<= 120% of trailing low (certified split-adjusted live window)
Positive book equity / market capitalization+1.4759; #935/6449 (top 14.5%)
✓AsnessTop 30% of eligible cross-section
Price / Diluted EPS6.7x
✓NeffP/E <= 15x (app proxy for a P/E 40%-60% below the market)
(EPS CAGR % + Dividend Yield %) / P/E
✗Neff> 0.7 (Neff's published traditional edge)
Price / Tangible Book Value per Share54.25x
✗SchlossP/TBV <= 1.00x (app cutoff)
Book Value per Share Change-45.8%
✗SchlossLatest BVPS >= earliest BVPS over >= 3 years (app rule)
Revenue / market capitalization+3.0411; #802/5247 (top 15.3%)
✗OshaughnessyTop 10% of eligible cross-section
(Operating cash flow - capex) / market capitalization-11.05%; #3274/4519 (top 72.4%)
✗OshaughnessyTop 10% of eligible cross-section
Trailing six-month price return through the evaluation date-40.49%; #4819/6202 (top 77.7%)
✗OshaughnessyTop 10% of eligible cross-section
Cash Flow50% pass✓ 7✗ 5▾
5 of 10 pass — Buffett, Lynch, Ackman +2 more object
Free Cash Flow Proxy
✗BuffettPositive and growing
FCF Positive and Growing$-29.1M
✗LynchPositive and growing
Operating Cash Flow$51.4M
✓PiotroskiCFO > 0
(CFO / Total Assets) vs ROACFO/Assets=4.24%, ROA=3.27%
✓PiotroskiCFO/Assets > ROA
Price / (CFO / Shares)5.0x
✓Dreman< 8x
P/E or FCF YieldP/E=6.7x, FCF Yield=9.9%
✓PabraiP/E < 15 or FCF Yield > 10%
FCF Positive9/11 years FCF positive
✓MarksPositive FCF in majority of recent years
(OCF - CapEx) / Market Cap-11.3%
✗Ackman>= 4%
Price / FCF per Share9.9x
✓Ackman<= 25
Positive Operating Cash Flow frequency9/11 years positive
✓SleepPositive OCF in >= 70% of available years
Operating Cash Flow - Capital Expenditures$-29.1M
✗Neff> $0 (app proxy for a strong fundamental case)
(Operating cash flow - capex) / market capitalization-11.05%; #3274/4519 (top 72.4%)
✗OshaughnessyTop 10% of eligible cross-section

Business & financials

Financial snapshot: annual FY 2025. Current investor scores may use newer quarterly data.

Company Profile

Industry: Business Services

Size: Micro Cap($263.4M)

Revenue: $844.6M+1.3% YoY

Net Income: $39.6M+173.1% YoY

Financial Snapshot

Operating Margin-0.4%

Return on Equity8.8%

Debt / Equity0.74

Current Ratio1.44

EPS (Diluted)$0.22

Buybacks (1y)$9.0M

Shares Retired0.1% / −1.8% 2y

Similar Companies

No peer companies found in this industry.

Shareholder Return

Fiscal 2025

Retired 0.1% of shares last year, 1.8% issued over two.

Buybacks: $9.0M
Dividends: —

Company Financials

Latest TTM and quarters alongside annual years

TTM sums four consecutive quarters and uses the latest quarter-end balances. Quarter columns show three-month results; annual columns show full-year totals. Growth compares the same period a year earlier. EPS is not added for TTM; full-year ratios are blank for quarters.

The latest annual period end is unavailable. Showing the latest fiscal cycle’s quarters; quarter and annual columns may overlap. Quarterly shows the full quarter history.

Metric	TTM · 2026-09-30 2025-10-01 – 2026-09-30 Sources · derived quarter values 10-K · 2026-02-26 10-Q · 2026-05-06 10-Q · 2026-07-31 10-Q · 2026-10-28 Derived from cumulative filings: revenue, net income, operating income, gross profit, ebit, pre tax income, operating cash flow, capex, buybacks.	Q3 FY 2026 2026-07-01 – 2026-09-30 Sources · derived quarter values 10-Q · 2026-10-28 Derived from cumulative filings: operating cash flow, capex, buybacks.	Q2 FY 2026 2026-04-01 – 2026-06-30 Sources · derived quarter values 10-Q · 2026-07-31 Derived from cumulative filings: operating cash flow, capex, buybacks.	Q1 FY 2026 2026-01-01 – 2026-03-31 Sources 10-Q · 2026-05-06	FY 2025 Sources 10-K · 2026-02-26	FY 2024 Sources 10-K · 2025-02-27	FY 2023 Sources 10-K · 2024-02-28	FY 2022 Sources 10-K · 2023-03-31	FY 2021 Sources 10-K · 2022-03-11
Market Cap	$263.4Mcurrent	--	--	--	$460.1Mest.	$720.5Mest.	$524.3Mest.	$594.0Mest.	$670.3Mest.
Revenue	$801.0M↓8%	$218.7M↑2%	$192.3M↓13%	$162.6M↓10%	$844.6M↑1%	$833.9M↑1%	$826.3M↑1%	$819.8M↓3%	$845.0M
Operating Income	-$29.0M↓241%	$5.6M↑103%	-$12.2M↓389%	-$31.7M↓62%	-$3.3M↓120%	$16.9M↑169%	-$24.3M↑50%	-$48.3M↑59%	-$117.8M
Net Income	$18.6M↑143%	-$9.1M↑25%	-$26.9M↓142%	-$34.5M↓32%	$39.6M↑173%	-$54.2M↑18%	-$66.2M↑33%	-$98.1M↑45%	-$177.2M
EPS (Diluted)	--	$-0.05↑29%	$-0.15↓150%	$-0.20↓33%	$0.22↑171%	$-0.31↑21%	$-0.39↑38%	$-0.63↑48%	$-1.20
Gross Margin	48.3%↓5%	48.2%↓4%	47.0%↓5%	42.9%↓6%	49.8%↓5%	52.7%↑7%	49.4%↑1%	48.9%↓7%	52.6%
Operating Margin	-3.6%↓253%	2.6%↑99%	-6.4%↓432%	-19.5%↓80%	-0.4%↓119%	2.0%↑169%	-2.9%↑50%	-5.9%↑58%	-13.9%
ROE	4.8%↑140%	—	—	—	8.8%↑166%	-13.4%↑8%	-14.6%↑23%	-18.9%↑44%	-33.6%
Total Debt	$327.9M↓2%	$327.9M↓2%	$329.4M↓2%	$331.7M↓1%	$333.3M↓1%	$336.9M↑45%	$232.6M↓29%	$326.3M↓12%	$370.3M
Shareholders' Equity	$388.7M↑8%	$388.7M↑8%	$392.6M↑6%	$419.1M↑10%	$449.0M↑11%	$404.6M↓11%	$452.8M↓13%	$518.4M↓2%	$527.2M
Current Ratio	1.32↓8%	1.32↓8%	1.31↓5%	1.37↓2%	1.44↑2%	1.41↑15%	1.23↓15%	1.45↑4%	1.40
Debt / Equity	0.84↓9%	0.84↓9%	0.84↓8%	0.79↓10%	0.74↓11%	0.83↑62%	0.51↓18%	0.63↓10%	0.70
Operating Cash Flow	-$18.7M↓122%	-$14.4M↓154%	-$11.5M↓1347%	-$22.0M↓522%	$51.4M↑2%	$50.2M↑194%	$17.1M↑165%	-$26.4M↓237%	$19.2M
Free Cash Flow	-$29.1M↓155%	-$15.5M↓174%	-$15.8M↓144%	-$25.1M↓60%	$26.1M↓6%	$27.8M↑261%	$7.7M↑121%	-$36.6M↓1886%	$2.0M